Move tests and fakes to webrtc namespace

- fake_video_renderer.h
- mock_channel_interface.h
- fake_network.h
- test_utils.h
- fake_webrtc_call.h
- fake_clock.h
- srtp_test_util.h
- fake_dtls_transport.h
- fake_network_interface.h
- fake_frame_source.h
- mock_packet_socket_factory.h
- fake_ssl_identity.h

Bug: webrtc:42232595
Change-Id: Ia363a95b7956d7c92fb87e4cf684bffe92c81409
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/381403
Commit-Queue: Harald Alvestrand <hta@webrtc.org>
Auto-Submit: Evan Shrubsole <eshr@webrtc.org>
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#44141}
diff --git a/api/test/mock_packet_socket_factory.h b/api/test/mock_packet_socket_factory.h
index 0e4a42c..0974297 100644
--- a/api/test/mock_packet_socket_factory.h
+++ b/api/test/mock_packet_socket_factory.h
@@ -21,24 +21,24 @@
 #include "rtc_base/socket_address.h"
 #include "test/gmock.h"
 
-namespace rtc {
-class MockPacketSocketFactory : public PacketSocketFactory {
+namespace webrtc {
+class MockPacketSocketFactory : public rtc::PacketSocketFactory {
  public:
-  MOCK_METHOD(AsyncPacketSocket*,
+  MOCK_METHOD(rtc::AsyncPacketSocket*,
               CreateUdpSocket,
-              (const webrtc::SocketAddress&, uint16_t, uint16_t),
+              (const SocketAddress&, uint16_t, uint16_t),
               (override));
-  MOCK_METHOD(AsyncListenSocket*,
+  MOCK_METHOD(rtc::AsyncListenSocket*,
               CreateServerTcpSocket,
-              (const webrtc::SocketAddress&, uint16_t, uint16_t, int opts),
+              (const SocketAddress&, uint16_t, uint16_t, int opts),
               (override));
-  MOCK_METHOD(AsyncPacketSocket*,
+  MOCK_METHOD(rtc::AsyncPacketSocket*,
               CreateClientTcpSocket,
-              (const webrtc::SocketAddress& local_address,
-               const webrtc::SocketAddress&,
-               const PacketSocketTcpOptions&),
+              (const SocketAddress& local_address,
+               const SocketAddress&,
+               const rtc::PacketSocketTcpOptions&),
               (override));
-  MOCK_METHOD(std::unique_ptr<webrtc::AsyncDnsResolverInterface>,
+  MOCK_METHOD(std::unique_ptr<AsyncDnsResolverInterface>,
               CreateAsyncDnsResolver,
               (),
               (override));
@@ -46,6 +46,12 @@
 
 static_assert(!std::is_abstract_v<MockPacketSocketFactory>, "");
 
+}  //  namespace webrtc
+
+// Re-export symbols from the webrtc namespace for backwards compatibility.
+// TODO(bugs.webrtc.org/4222596): Remove once all references are updated.
+namespace rtc {
+using ::webrtc::MockPacketSocketFactory;
 }  // namespace rtc
 
 #endif  // API_TEST_MOCK_PACKET_SOCKET_FACTORY_H_
diff --git a/api/video_codecs/test/video_encoder_software_fallback_wrapper_unittest.cc b/api/video_codecs/test/video_encoder_software_fallback_wrapper_unittest.cc
index c08b3e4..2d87df8 100644
--- a/api/video_codecs/test/video_encoder_software_fallback_wrapper_unittest.cc
+++ b/api/video_codecs/test/video_encoder_software_fallback_wrapper_unittest.cc
@@ -555,7 +555,7 @@
     CheckLastEncoderName(expected_name);
   }
 
-  rtc::ScopedFakeClock clock_;
+  ScopedFakeClock clock_;
 };
 
 class ForcedFallbackTestEnabled : public ForcedFallbackTest {
diff --git a/common_audio/smoothing_filter_unittest.cc b/common_audio/smoothing_filter_unittest.cc
index 47f6c71..01bfa56 100644
--- a/common_audio/smoothing_filter_unittest.cc
+++ b/common_audio/smoothing_filter_unittest.cc
@@ -28,7 +28,7 @@
       : smoothing_filter(init_time_ms) {
     fake_clock.AdvanceTime(TimeDelta::Millis(kClockInitialTime));
   }
-  rtc::ScopedFakeClock fake_clock;
+  ScopedFakeClock fake_clock;
   SmoothingFilterImpl smoothing_filter;
 };
 
diff --git a/common_video/bitrate_adjuster_unittest.cc b/common_video/bitrate_adjuster_unittest.cc
index 995aac1..1ff911c 100644
--- a/common_video/bitrate_adjuster_unittest.cc
+++ b/common_video/bitrate_adjuster_unittest.cc
@@ -64,7 +64,7 @@
  protected:
   static const float kMinAdjustedBitratePct;
   static const float kMaxAdjustedBitratePct;
-  rtc::ScopedFakeClock clock_;
+  ScopedFakeClock clock_;
   BitrateAdjuster adjuster_;
 };
 
diff --git a/logging/rtc_event_log/encoder/rtc_event_log_encoder_unittest.cc b/logging/rtc_event_log/encoder/rtc_event_log_encoder_unittest.cc
index 8043619..af0c2c2 100644
--- a/logging/rtc_event_log/encoder/rtc_event_log_encoder_unittest.cc
+++ b/logging/rtc_event_log/encoder/rtc_event_log_encoder_unittest.cc
@@ -972,7 +972,7 @@
     return;
   }
 
-  rtc::ScopedFakeClock fake_clock;
+  ScopedFakeClock fake_clock;
   fake_clock.SetTime(Timestamp::Millis(prng_.Rand<uint32_t>()));
 
   std::unique_ptr<RtcEventLogEncoder> encoder = CreateEncoder();
@@ -1012,7 +1012,7 @@
     return;
   }
 
-  rtc::ScopedFakeClock fake_clock;
+  ScopedFakeClock fake_clock;
   fake_clock.SetTime(Timestamp::Millis(prng_.Rand<uint32_t>()));
 
   std::unique_ptr<RtcEventLogEncoder> encoder = CreateEncoder();
@@ -1052,7 +1052,7 @@
     return;
   }
 
-  rtc::ScopedFakeClock fake_clock;
+  ScopedFakeClock fake_clock;
   fake_clock.SetTime(Timestamp::Millis(prng_.Rand<uint32_t>()));
 
   std::unique_ptr<RtcEventLogEncoder> encoder = CreateEncoder();
@@ -1092,7 +1092,7 @@
     return;
   }
 
-  rtc::ScopedFakeClock fake_clock;
+  ScopedFakeClock fake_clock;
   fake_clock.SetTime(Timestamp::Millis(prng_.Rand<uint32_t>()));
 
   std::unique_ptr<RtcEventLogEncoder> encoder = CreateEncoder();
@@ -1131,7 +1131,7 @@
     return;
   }
 
-  rtc::ScopedFakeClock fake_clock;
+  ScopedFakeClock fake_clock;
   fake_clock.SetTime(Timestamp::Millis(prng_.Rand<uint32_t>()));
 
   std::unique_ptr<RtcEventLogEncoder> encoder = CreateEncoder();
@@ -1170,7 +1170,7 @@
     return;
   }
 
-  rtc::ScopedFakeClock fake_clock;
+  ScopedFakeClock fake_clock;
   fake_clock.SetTime(Timestamp::Millis(prng_.Rand<uint32_t>()));
 
   std::unique_ptr<RtcEventLogEncoder> encoder = CreateEncoder();
@@ -1209,7 +1209,7 @@
     return;
   }
 
-  rtc::ScopedFakeClock fake_clock;
+  ScopedFakeClock fake_clock;
   fake_clock.SetTime(Timestamp::Millis(prng_.Rand<uint32_t>()));
 
   std::unique_ptr<RtcEventLogEncoder> encoder = CreateEncoder();
@@ -1248,7 +1248,7 @@
     return;
   }
 
-  rtc::ScopedFakeClock fake_clock;
+  ScopedFakeClock fake_clock;
   fake_clock.SetTime(Timestamp::Millis(prng_.Rand<uint32_t>()));
 
   std::unique_ptr<RtcEventLogEncoder> encoder = CreateEncoder();
@@ -1287,7 +1287,7 @@
     return;
   }
 
-  rtc::ScopedFakeClock fake_clock;
+  ScopedFakeClock fake_clock;
   fake_clock.SetTime(Timestamp::Millis(prng_.Rand<uint32_t>()));
 
   std::unique_ptr<RtcEventLogEncoder> encoder = CreateEncoder();
@@ -1329,7 +1329,7 @@
     return;
   }
 
-  rtc::ScopedFakeClock fake_clock;
+  ScopedFakeClock fake_clock;
   fake_clock.SetTime(Timestamp::Millis(prng_.Rand<uint32_t>()));
 
   std::unique_ptr<RtcEventLogEncoder> encoder = CreateEncoder();
diff --git a/logging/rtc_event_log/rtc_event_log_unittest.cc b/logging/rtc_event_log/rtc_event_log_unittest.cc
index eafe857..6c57e9d 100644
--- a/logging/rtc_event_log/rtc_event_log_unittest.cc
+++ b/logging/rtc_event_log/rtc_event_log_unittest.cc
@@ -234,7 +234,7 @@
   const RtcEventLog::EncodingType encoding_type_;
   test::EventGenerator gen_;
   test::EventVerifier verifier_;
-  rtc::ScopedFakeClock clock_;
+  ScopedFakeClock clock_;
   std::string temp_filename_;
   MemoryLogStorage log_storage_;
   std::unique_ptr<LogWriterFactoryInterface> log_output_factory_;
@@ -952,8 +952,8 @@
   std::replace(test_name.begin(), test_name.end(), '/', '_');
   const std::string temp_filename = test::OutputPath() + test_name;
 
-  std::unique_ptr<rtc::ScopedFakeClock> fake_clock =
-      std::make_unique<rtc::ScopedFakeClock>();
+  std::unique_ptr<ScopedFakeClock> fake_clock =
+      std::make_unique<ScopedFakeClock>();
   fake_clock->SetTime(Timestamp::Seconds(kStartTimeSeconds));
 
   // Create a scope for the TQ and event log factories.
@@ -1017,7 +1017,7 @@
   // recreate the clock. However we must ensure that the old fake_clock is
   // destroyed before the new one is created, so we have to reset() first.
   fake_clock.reset();
-  fake_clock = std::make_unique<rtc::ScopedFakeClock>();
+  fake_clock = std::make_unique<ScopedFakeClock>();
   fake_clock->SetTime(Timestamp::Millis(first_timestamp_ms));
   for (size_t i = 1; i < probe_success_events.size(); i++) {
     fake_clock->AdvanceTime(TimeDelta::Millis(10));
diff --git a/media/base/fake_frame_source.cc b/media/base/fake_frame_source.cc
index 61bc585..a94de3b 100644
--- a/media/base/fake_frame_source.cc
+++ b/media/base/fake_frame_source.cc
@@ -16,7 +16,7 @@
 #include "rtc_base/checks.h"
 #include "rtc_base/time_utils.h"
 
-namespace cricket {
+namespace webrtc {
 
 FakeFrameSource::FakeFrameSource(int width,
                                  int height,
@@ -35,15 +35,15 @@
 FakeFrameSource::FakeFrameSource(int width, int height, int interval_us)
     : FakeFrameSource(width, height, interval_us, rtc::TimeMicros()) {}
 
-webrtc::VideoRotation FakeFrameSource::GetRotation() const {
+VideoRotation FakeFrameSource::GetRotation() const {
   return rotation_;
 }
 
-void FakeFrameSource::SetRotation(webrtc::VideoRotation rotation) {
+void FakeFrameSource::SetRotation(VideoRotation rotation) {
   rotation_ = rotation;
 }
 
-webrtc::VideoFrame FakeFrameSource::GetFrameRotationApplied() {
+VideoFrame FakeFrameSource::GetFrameRotationApplied() {
   switch (rotation_) {
     case webrtc::kVideoRotation_0:
     case webrtc::kVideoRotation_180:
@@ -59,30 +59,29 @@
   return GetFrame();
 }
 
-webrtc::VideoFrame FakeFrameSource::GetFrame() {
+VideoFrame FakeFrameSource::GetFrame() {
   return GetFrame(width_, height_, rotation_, interval_us_);
 }
 
-webrtc::VideoFrame FakeFrameSource::GetFrame(int width,
-                                             int height,
-                                             webrtc::VideoRotation rotation,
-                                             int interval_us) {
+VideoFrame FakeFrameSource::GetFrame(int width,
+                                     int height,
+                                     VideoRotation rotation,
+                                     int interval_us) {
   RTC_CHECK_GT(width, 0);
   RTC_CHECK_GT(height, 0);
   RTC_CHECK_GT(interval_us, 0);
 
-  rtc::scoped_refptr<webrtc::I420Buffer> buffer(
-      webrtc::I420Buffer::Create(width, height));
+  scoped_refptr<I420Buffer> buffer(I420Buffer::Create(width, height));
 
   buffer->InitializeData();
-  webrtc::VideoFrame frame = webrtc::VideoFrame::Builder()
-                                 .set_video_frame_buffer(buffer)
-                                 .set_rotation(rotation)
-                                 .set_timestamp_us(next_timestamp_us_)
-                                 .build();
+  VideoFrame frame = VideoFrame::Builder()
+                         .set_video_frame_buffer(buffer)
+                         .set_rotation(rotation)
+                         .set_timestamp_us(next_timestamp_us_)
+                         .build();
 
   next_timestamp_us_ += interval_us;
   return frame;
 }
 
-}  // namespace cricket
+}  // namespace webrtc
diff --git a/media/base/fake_frame_source.h b/media/base/fake_frame_source.h
index 4c56204..e1bd0b2 100644
--- a/media/base/fake_frame_source.h
+++ b/media/base/fake_frame_source.h
@@ -14,7 +14,7 @@
 #include "api/video/video_frame.h"
 #include "rtc_base/time_utils.h"
 
-namespace cricket {
+namespace webrtc {
 
 class FakeFrameSource {
  public:
@@ -24,27 +24,33 @@
                   int64_t timestamp_offset_us);
   FakeFrameSource(int width, int height, int interval_us);
 
-  webrtc::VideoRotation GetRotation() const;
-  void SetRotation(webrtc::VideoRotation rotation);
+  VideoRotation GetRotation() const;
+  void SetRotation(VideoRotation rotation);
 
-  webrtc::VideoFrame GetFrame();
-  webrtc::VideoFrame GetFrameRotationApplied();
+  VideoFrame GetFrame();
+  VideoFrame GetFrameRotationApplied();
 
   // Override configuration.
-  webrtc::VideoFrame GetFrame(int width,
-                              int height,
-                              webrtc::VideoRotation rotation,
-                              int interval_us);
+  VideoFrame GetFrame(int width,
+                      int height,
+                      VideoRotation rotation,
+                      int interval_us);
 
  private:
   const int width_;
   const int height_;
   const int interval_us_;
 
-  webrtc::VideoRotation rotation_ = webrtc::kVideoRotation_0;
+  VideoRotation rotation_ = webrtc::kVideoRotation_0;
   int64_t next_timestamp_us_;
 };
 
+}  //  namespace webrtc
+
+// Re-export symbols from the webrtc namespace for backwards compatibility.
+// TODO(bugs.webrtc.org/4222596): Remove once all references are updated.
+namespace cricket {
+using ::webrtc::FakeFrameSource;
 }  // namespace cricket
 
 #endif  // MEDIA_BASE_FAKE_FRAME_SOURCE_H_
diff --git a/media/base/fake_network_interface.h b/media/base/fake_network_interface.h
index fba7f9d..678da58 100644
--- a/media/base/fake_network_interface.h
+++ b/media/base/fake_network_interface.h
@@ -30,10 +30,10 @@
 #include "rtc_base/thread.h"
 #include "rtc_base/time_utils.h"
 
-namespace cricket {
+namespace webrtc {
 
 // Fake NetworkInterface that sends/receives RTP/RTCP packets.
-class FakeNetworkInterface : public MediaChannelNetworkInterface {
+class FakeNetworkInterface : public cricket::MediaChannelNetworkInterface {
  public:
   FakeNetworkInterface()
       : thread_(rtc::Thread::Current()),
@@ -43,20 +43,22 @@
         recvbuf_size_(-1),
         dscp_(rtc::DSCP_NO_CHANGE) {}
 
-  void SetDestination(MediaReceiveChannelInterface* dest) { dest_ = dest; }
+  void SetDestination(cricket::MediaReceiveChannelInterface* dest) {
+    dest_ = dest;
+  }
 
   // Conference mode is a mode where instead of simply forwarding the packets,
   // the transport will send multiple copies of the packet with the specified
   // SSRCs. This allows us to simulate receiving media from multiple sources.
   void SetConferenceMode(bool conf, const std::vector<uint32_t>& ssrcs)
       RTC_LOCKS_EXCLUDED(mutex_) {
-    webrtc::MutexLock lock(&mutex_);
+    MutexLock lock(&mutex_);
     conf_ = conf;
     conf_sent_ssrcs_ = ssrcs;
   }
 
   int NumRtpBytes() RTC_LOCKS_EXCLUDED(mutex_) {
-    webrtc::MutexLock lock(&mutex_);
+    MutexLock lock(&mutex_);
     int bytes = 0;
     for (size_t i = 0; i < rtp_packets_.size(); ++i) {
       bytes += static_cast<int>(rtp_packets_[i].size());
@@ -65,31 +67,31 @@
   }
 
   int NumRtpBytes(uint32_t ssrc) RTC_LOCKS_EXCLUDED(mutex_) {
-    webrtc::MutexLock lock(&mutex_);
+    MutexLock lock(&mutex_);
     int bytes = 0;
     GetNumRtpBytesAndPackets(ssrc, &bytes, NULL);
     return bytes;
   }
 
   int NumRtpPackets() RTC_LOCKS_EXCLUDED(mutex_) {
-    webrtc::MutexLock lock(&mutex_);
+    MutexLock lock(&mutex_);
     return static_cast<int>(rtp_packets_.size());
   }
 
   int NumRtpPackets(uint32_t ssrc) RTC_LOCKS_EXCLUDED(mutex_) {
-    webrtc::MutexLock lock(&mutex_);
+    MutexLock lock(&mutex_);
     int packets = 0;
     GetNumRtpBytesAndPackets(ssrc, NULL, &packets);
     return packets;
   }
 
   int NumSentSsrcs() RTC_LOCKS_EXCLUDED(mutex_) {
-    webrtc::MutexLock lock(&mutex_);
+    MutexLock lock(&mutex_);
     return static_cast<int>(sent_ssrcs_.size());
   }
 
-  rtc::CopyOnWriteBuffer GetRtpPacket(int index) RTC_LOCKS_EXCLUDED(mutex_) {
-    webrtc::MutexLock lock(&mutex_);
+  CopyOnWriteBuffer GetRtpPacket(int index) RTC_LOCKS_EXCLUDED(mutex_) {
+    MutexLock lock(&mutex_);
     if (index >= static_cast<int>(rtp_packets_.size())) {
       return {};
     }
@@ -97,18 +99,17 @@
   }
 
   int NumRtcpPackets() RTC_LOCKS_EXCLUDED(mutex_) {
-    webrtc::MutexLock lock(&mutex_);
+    MutexLock lock(&mutex_);
     return static_cast<int>(rtcp_packets_.size());
   }
 
   // Note: callers are responsible for deleting the returned buffer.
-  const rtc::CopyOnWriteBuffer* GetRtcpPacket(int index)
-      RTC_LOCKS_EXCLUDED(mutex_) {
-    webrtc::MutexLock lock(&mutex_);
+  const CopyOnWriteBuffer* GetRtcpPacket(int index) RTC_LOCKS_EXCLUDED(mutex_) {
+    MutexLock lock(&mutex_);
     if (index >= static_cast<int>(rtcp_packets_.size())) {
       return NULL;
     }
-    return new rtc::CopyOnWriteBuffer(rtcp_packets_[index]);
+    return new CopyOnWriteBuffer(rtcp_packets_[index]);
   }
 
   int sendbuf_size() const { return sendbuf_size_; }
@@ -117,14 +118,14 @@
   rtc::PacketOptions options() const { return options_; }
 
  protected:
-  virtual bool SendPacket(rtc::CopyOnWriteBuffer* packet,
+  virtual bool SendPacket(CopyOnWriteBuffer* packet,
                           const rtc::PacketOptions& options)
       RTC_LOCKS_EXCLUDED(mutex_) {
     if (!webrtc::IsRtpPacket(*packet)) {
       return false;
     }
 
-    webrtc::MutexLock lock(&mutex_);
+    MutexLock lock(&mutex_);
     sent_ssrcs_[webrtc::ParseRtpSsrc(*packet)]++;
     options_ = options;
 
@@ -140,10 +141,10 @@
     return true;
   }
 
-  virtual bool SendRtcp(rtc::CopyOnWriteBuffer* packet,
+  virtual bool SendRtcp(CopyOnWriteBuffer* packet,
                         const rtc::PacketOptions& options)
       RTC_LOCKS_EXCLUDED(mutex_) {
-    webrtc::MutexLock lock(&mutex_);
+    MutexLock lock(&mutex_);
     rtcp_packets_.push_back(*packet);
     options_ = options;
     if (!conf_) {
@@ -167,24 +168,23 @@
     return 0;
   }
 
-  void PostPacket(rtc::CopyOnWriteBuffer packet) {
-    thread_->PostTask(
-        SafeTask(safety_.flag(), [this, packet = std::move(packet)]() mutable {
-          if (dest_) {
-            webrtc::RtpPacketReceived parsed_packet;
-            if (parsed_packet.Parse(packet)) {
-              parsed_packet.set_arrival_time(
-                  webrtc::Timestamp::Micros(rtc::TimeMicros()));
-              dest_->OnPacketReceived(std::move(parsed_packet));
-            } else {
-              RTC_DCHECK_NOTREACHED();
-            }
-          }
-        }));
+  void PostPacket(CopyOnWriteBuffer packet) {
+    thread_->PostTask(SafeTask(safety_.flag(), [this, packet = std::move(
+                                                          packet)]() mutable {
+      if (dest_) {
+        RtpPacketReceived parsed_packet;
+        if (parsed_packet.Parse(packet)) {
+          parsed_packet.set_arrival_time(Timestamp::Micros(rtc::TimeMicros()));
+          dest_->OnPacketReceived(std::move(parsed_packet));
+        } else {
+          RTC_DCHECK_NOTREACHED();
+        }
+      }
+    }));
   }
 
  private:
-  void SetRtpSsrc(uint32_t ssrc, rtc::CopyOnWriteBuffer& buffer) {
+  void SetRtpSsrc(uint32_t ssrc, CopyOnWriteBuffer& buffer) {
     RTC_CHECK_GE(buffer.size(), 12);
     webrtc::SetBE32(buffer.MutableData() + 8, ssrc);
   }
@@ -208,8 +208,8 @@
     }
   }
 
-  webrtc::TaskQueueBase* thread_;
-  MediaReceiveChannelInterface* dest_;
+  TaskQueueBase* thread_;
+  cricket::MediaReceiveChannelInterface* dest_;
   bool conf_;
   // The ssrcs used in sending out packets in conference mode.
   std::vector<uint32_t> conf_sent_ssrcs_;
@@ -218,17 +218,23 @@
   std::map<uint32_t, uint32_t> sent_ssrcs_;
   // Map to track packet-number that needs to be dropped per ssrc.
   std::map<uint32_t, std::set<uint32_t> > drop_map_;
-  webrtc::Mutex mutex_;
-  std::vector<rtc::CopyOnWriteBuffer> rtp_packets_;
-  std::vector<rtc::CopyOnWriteBuffer> rtcp_packets_;
+  Mutex mutex_;
+  std::vector<CopyOnWriteBuffer> rtp_packets_;
+  std::vector<CopyOnWriteBuffer> rtcp_packets_;
   int sendbuf_size_;
   int recvbuf_size_;
   rtc::DiffServCodePoint dscp_;
   // Options of the most recently sent packet.
   rtc::PacketOptions options_;
-  webrtc::ScopedTaskSafety safety_;
+  ScopedTaskSafety safety_;
 };
 
+}  //  namespace webrtc
+
+// Re-export symbols from the webrtc namespace for backwards compatibility.
+// TODO(bugs.webrtc.org/4222596): Remove once all references are updated.
+namespace cricket {
+using ::webrtc::FakeNetworkInterface;
 }  // namespace cricket
 
 #endif  // MEDIA_BASE_FAKE_NETWORK_INTERFACE_H_
diff --git a/media/base/fake_video_renderer.cc b/media/base/fake_video_renderer.cc
index b235738..b307a99 100644
--- a/media/base/fake_video_renderer.cc
+++ b/media/base/fake_video_renderer.cc
@@ -10,9 +10,9 @@
 
 #include "media/base/fake_video_renderer.h"
 
-namespace cricket {
+namespace webrtc {
 namespace {
-bool CheckFrameColorYuv(const webrtc::VideoFrame& frame) {
+bool CheckFrameColorYuv(const VideoFrame& frame) {
   // TODO(zhurunz) Check with VP8 team to see if we can remove this
   // tolerance on Y values. Some unit tests produce Y values close
   // to 16 rather than close to zero, for supposedly black frames.
@@ -28,7 +28,7 @@
   if (!frame.video_frame_buffer()) {
     return false;
   }
-  rtc::scoped_refptr<const webrtc::I420BufferInterface> i420_buffer =
+  scoped_refptr<const I420BufferInterface> i420_buffer =
       frame.video_frame_buffer()->ToI420();
   // Y
   int y_width = frame.width();
@@ -74,8 +74,8 @@
 
 FakeVideoRenderer::FakeVideoRenderer() = default;
 
-void FakeVideoRenderer::OnFrame(const webrtc::VideoFrame& frame) {
-  webrtc::MutexLock lock(&mutex_);
+void FakeVideoRenderer::OnFrame(const VideoFrame& frame) {
+  MutexLock lock(&mutex_);
   black_frame_ = CheckFrameColorYuv(frame);
   ++num_rendered_frames_;
   width_ = frame.width();
@@ -84,4 +84,4 @@
   timestamp_us_ = frame.timestamp_us();
 }
 
-}  // namespace cricket
+}  // namespace webrtc
diff --git a/media/base/fake_video_renderer.h b/media/base/fake_video_renderer.h
index 33d99a2..74c8fc7 100644
--- a/media/base/fake_video_renderer.h
+++ b/media/base/fake_video_renderer.h
@@ -20,54 +20,60 @@
 #include "api/video/video_sink_interface.h"
 #include "rtc_base/synchronization/mutex.h"
 
-namespace cricket {
+namespace webrtc {
 
 // Faked video renderer that has a callback for actions on rendering.
-class FakeVideoRenderer : public rtc::VideoSinkInterface<webrtc::VideoFrame> {
+class FakeVideoRenderer : public rtc::VideoSinkInterface<VideoFrame> {
  public:
   FakeVideoRenderer();
 
-  void OnFrame(const webrtc::VideoFrame& frame) override;
+  void OnFrame(const VideoFrame& frame) override;
 
   int width() const {
-    webrtc::MutexLock lock(&mutex_);
+    MutexLock lock(&mutex_);
     return width_;
   }
   int height() const {
-    webrtc::MutexLock lock(&mutex_);
+    MutexLock lock(&mutex_);
     return height_;
   }
 
-  webrtc::VideoRotation rotation() const {
-    webrtc::MutexLock lock(&mutex_);
+  VideoRotation rotation() const {
+    MutexLock lock(&mutex_);
     return rotation_;
   }
 
   int64_t timestamp_us() const {
-    webrtc::MutexLock lock(&mutex_);
+    MutexLock lock(&mutex_);
     return timestamp_us_;
   }
 
   int num_rendered_frames() const {
-    webrtc::MutexLock lock(&mutex_);
+    MutexLock lock(&mutex_);
     return num_rendered_frames_;
   }
 
   bool black_frame() const {
-    webrtc::MutexLock lock(&mutex_);
+    MutexLock lock(&mutex_);
     return black_frame_;
   }
 
  private:
   int width_ = 0;
   int height_ = 0;
-  webrtc::VideoRotation rotation_ = webrtc::kVideoRotation_0;
+  VideoRotation rotation_ = webrtc::kVideoRotation_0;
   int64_t timestamp_us_ = 0;
   int num_rendered_frames_ = 0;
   bool black_frame_ = false;
-  mutable webrtc::Mutex mutex_;
+  mutable Mutex mutex_;
 };
 
+}  //  namespace webrtc
+
+// Re-export symbols from the webrtc namespace for backwards compatibility.
+// TODO(bugs.webrtc.org/4222596): Remove once all references are updated.
+namespace cricket {
+using ::webrtc::FakeVideoRenderer;
 }  // namespace cricket
 
 #endif  // MEDIA_BASE_FAKE_VIDEO_RENDERER_H_
diff --git a/media/base/test_utils.cc b/media/base/test_utils.cc
index 1b28873..dc33d55 100644
--- a/media/base/test_utils.cc
+++ b/media/base/test_utils.cc
@@ -15,7 +15,7 @@
 #include "api/video/video_frame.h"
 #include "api/video/video_source_interface.h"
 
-namespace cricket {
+namespace webrtc {
 
 cricket::StreamParams CreateSimStreamParams(
     const std::string& cname,
@@ -52,4 +52,4 @@
   return sp;
 }
 
-}  // namespace cricket
+}  // namespace webrtc
diff --git a/media/base/test_utils.h b/media/base/test_utils.h
index dc14e44..f968c6e 100644
--- a/media/base/test_utils.h
+++ b/media/base/test_utils.h
@@ -22,7 +22,7 @@
 class VideoFrame;
 }
 
-namespace cricket {
+namespace webrtc {
 
 // Returns size of 420 image with rounding on chroma for odd sizes.
 #define I420_SIZE(w, h) (w * h + (((w + 1) / 2) * ((h + 1) / 2)) * 2)
@@ -33,7 +33,7 @@
 inline std::vector<T> MakeVector(const T a[], size_t s) {
   return std::vector<T>(a, a + s);
 }
-#define MAKE_VECTOR(a) cricket::MakeVector(a, arraysize(a))
+#define MAKE_VECTOR(a) webrtc::MakeVector(a, arraysize(a))
 
 // Create Simulcast StreamParams with given `ssrcs` and `cname`.
 cricket::StreamParams CreateSimStreamParams(const std::string& cname,
@@ -51,6 +51,15 @@
     uint32_t primary_ssrc,
     uint32_t flexfec_ssrc);
 
+}  //  namespace webrtc
+
+// Re-export symbols from the webrtc namespace for backwards compatibility.
+// TODO(bugs.webrtc.org/4222596): Remove once all references are updated.
+namespace cricket {
+using ::webrtc::CreatePrimaryWithFecFrStreamParams;
+using ::webrtc::CreateSimStreamParams;
+using ::webrtc::CreateSimWithRtxStreamParams;
+using ::webrtc::MakeVector;
 }  // namespace cricket
 
 #endif  // MEDIA_BASE_TEST_UTILS_H_
diff --git a/media/base/video_adapter_unittest.cc b/media/base/video_adapter_unittest.cc
index e1a8055..1bd974b 100644
--- a/media/base/video_adapter_unittest.cc
+++ b/media/base/video_adapter_unittest.cc
@@ -77,7 +77,7 @@
   explicit VideoAdapterTest(const std::string& field_trials,
                             int source_resolution_alignment)
       : override_field_trials_(field_trials),
-        frame_source_(std::make_unique<FakeFrameSource>(
+        frame_source_(std::make_unique<webrtc::FakeFrameSource>(
             kWidth,
             kHeight,
             VideoFormat::FpsToInterval(kDefaultFps) /
@@ -176,7 +176,7 @@
   }
 
   webrtc::test::ScopedFieldTrials override_field_trials_;
-  const std::unique_ptr<FakeFrameSource> frame_source_;
+  const std::unique_ptr<webrtc::FakeFrameSource> frame_source_;
   VideoAdapter adapter_;
   int64_t timestamp_ns_ = 0;
   int cropped_width_;
diff --git a/media/base/video_broadcaster_unittest.cc b/media/base/video_broadcaster_unittest.cc
index b75b42e..e05117e 100644
--- a/media/base/video_broadcaster_unittest.cc
+++ b/media/base/video_broadcaster_unittest.cc
@@ -21,9 +21,9 @@
 #include "test/gmock.h"
 #include "test/gtest.h"
 
-using cricket::FakeVideoRenderer;
 using rtc::VideoBroadcaster;
 using rtc::VideoSinkWants;
+using ::webrtc::FakeVideoRenderer;
 using FrameSize = rtc::VideoSinkWants::FrameSize;
 
 using ::testing::AllOf;
diff --git a/media/engine/fake_webrtc_call.cc b/media/engine/fake_webrtc_call.cc
index f866060..f4543bd 100644
--- a/media/engine/fake_webrtc_call.cc
+++ b/media/engine/fake_webrtc_call.cc
@@ -56,29 +56,26 @@
 #include "video/config/encoder_stream_factory.h"
 #include "video/config/video_encoder_config.h"
 
-namespace cricket {
+namespace webrtc {
 
 using ::webrtc::Environment;
 using ::webrtc::ParseRtpSsrc;
 
-FakeAudioSendStream::FakeAudioSendStream(
-    int id,
-    const webrtc::AudioSendStream::Config& config)
+FakeAudioSendStream::FakeAudioSendStream(int id,
+                                         const AudioSendStream::Config& config)
     : id_(id), config_(config) {}
 
-void FakeAudioSendStream::Reconfigure(
-    const webrtc::AudioSendStream::Config& config,
-    webrtc::SetParametersCallback callback) {
+void FakeAudioSendStream::Reconfigure(const AudioSendStream::Config& config,
+                                      SetParametersCallback callback) {
   config_ = config;
-  webrtc::InvokeSetParametersCallback(callback, webrtc::RTCError::OK());
+  webrtc::InvokeSetParametersCallback(callback, RTCError::OK());
 }
 
-const webrtc::AudioSendStream::Config& FakeAudioSendStream::GetConfig() const {
+const AudioSendStream::Config& FakeAudioSendStream::GetConfig() const {
   return config_;
 }
 
-void FakeAudioSendStream::SetStats(
-    const webrtc::AudioSendStream::Stats& stats) {
+void FakeAudioSendStream::SetStats(const AudioSendStream::Stats& stats) {
   stats_ = stats;
 }
 
@@ -102,33 +99,33 @@
   muted_ = muted;
 }
 
-webrtc::AudioSendStream::Stats FakeAudioSendStream::GetStats() const {
+AudioSendStream::Stats FakeAudioSendStream::GetStats() const {
   return stats_;
 }
 
-webrtc::AudioSendStream::Stats FakeAudioSendStream::GetStats(
+AudioSendStream::Stats FakeAudioSendStream::GetStats(
     bool /*has_remote_tracks*/) const {
   return stats_;
 }
 
 FakeAudioReceiveStream::FakeAudioReceiveStream(
     int id,
-    const webrtc::AudioReceiveStreamInterface::Config& config)
+    const AudioReceiveStreamInterface::Config& config)
     : id_(id), config_(config) {}
 
-const webrtc::AudioReceiveStreamInterface::Config&
-FakeAudioReceiveStream::GetConfig() const {
+const AudioReceiveStreamInterface::Config& FakeAudioReceiveStream::GetConfig()
+    const {
   return config_;
 }
 
 void FakeAudioReceiveStream::SetStats(
-    const webrtc::AudioReceiveStreamInterface::Stats& stats) {
+    const AudioReceiveStreamInterface::Stats& stats) {
   stats_ = stats;
 }
 
 bool FakeAudioReceiveStream::VerifyLastPacket(const uint8_t* data,
                                               size_t length) const {
-  return last_packet_ == rtc::Buffer(data, length);
+  return last_packet_ == Buffer(data, length);
 }
 
 bool FakeAudioReceiveStream::DeliverRtp(const uint8_t* packet,
@@ -140,12 +137,12 @@
 }
 
 void FakeAudioReceiveStream::SetDepacketizerToDecoderFrameTransformer(
-    rtc::scoped_refptr<webrtc::FrameTransformerInterface> frame_transformer) {
+    scoped_refptr<FrameTransformerInterface> frame_transformer) {
   config_.frame_transformer = std::move(frame_transformer);
 }
 
 void FakeAudioReceiveStream::SetDecoderMap(
-    std::map<int, webrtc::SdpAudioFormat> decoder_map) {
+    std::map<int, SdpAudioFormat> decoder_map) {
   config_.decoder_map = std::move(decoder_map);
 }
 
@@ -153,7 +150,7 @@
   config_.rtp.nack.rtp_history_ms = history_ms;
 }
 
-void FakeAudioReceiveStream::SetRtcpMode(webrtc::RtcpMode mode) {
+void FakeAudioReceiveStream::SetRtcpMode(RtcpMode mode) {
   config_.rtp.rtcp_mode = mode;
 }
 
@@ -162,16 +159,16 @@
 }
 
 void FakeAudioReceiveStream::SetFrameDecryptor(
-    rtc::scoped_refptr<webrtc::FrameDecryptorInterface> frame_decryptor) {
+    scoped_refptr<FrameDecryptorInterface> frame_decryptor) {
   config_.frame_decryptor = std::move(frame_decryptor);
 }
 
-webrtc::AudioReceiveStreamInterface::Stats FakeAudioReceiveStream::GetStats(
+AudioReceiveStreamInterface::Stats FakeAudioReceiveStream::GetStats(
     bool /* get_and_clear_legacy_stats */) const {
   return stats_;
 }
 
-void FakeAudioReceiveStream::SetSink(webrtc::AudioSinkInterface* sink) {
+void FakeAudioReceiveStream::SetSink(AudioSinkInterface* sink) {
   sink_ = sink;
 }
 
@@ -179,10 +176,9 @@
   gain_ = gain;
 }
 
-FakeVideoSendStream::FakeVideoSendStream(
-    const Environment& env,
-    webrtc::VideoSendStream::Config config,
-    webrtc::VideoEncoderConfig encoder_config)
+FakeVideoSendStream::FakeVideoSendStream(const Environment& env,
+                                         VideoSendStream::Config config,
+                                         VideoEncoderConfig encoder_config)
     : env_(env),
       sending_(false),
       config_(std::move(config)),
@@ -201,17 +197,15 @@
     source_->RemoveSink(this);
 }
 
-const webrtc::VideoSendStream::Config& FakeVideoSendStream::GetConfig() const {
+const VideoSendStream::Config& FakeVideoSendStream::GetConfig() const {
   return config_;
 }
 
-const webrtc::VideoEncoderConfig& FakeVideoSendStream::GetEncoderConfig()
-    const {
+const VideoEncoderConfig& FakeVideoSendStream::GetEncoderConfig() const {
   return encoder_config_;
 }
 
-const std::vector<webrtc::VideoStream>& FakeVideoSendStream::GetVideoStreams()
-    const {
+const std::vector<VideoStream>& FakeVideoSendStream::GetVideoStreams() const {
   return video_streams_;
 }
 
@@ -219,8 +213,7 @@
   return sending_;
 }
 
-bool FakeVideoSendStream::GetVp8Settings(
-    webrtc::VideoCodecVP8* settings) const {
+bool FakeVideoSendStream::GetVp8Settings(VideoCodecVP8* settings) const {
   if (!codec_settings_set_) {
     return false;
   }
@@ -229,8 +222,7 @@
   return true;
 }
 
-bool FakeVideoSendStream::GetVp9Settings(
-    webrtc::VideoCodecVP9* settings) const {
+bool FakeVideoSendStream::GetVp9Settings(VideoCodecVP9* settings) const {
   if (!codec_settings_set_) {
     return false;
   }
@@ -239,8 +231,7 @@
   return true;
 }
 
-bool FakeVideoSendStream::GetH264Settings(
-    webrtc::VideoCodecH264* settings) const {
+bool FakeVideoSendStream::GetH264Settings(VideoCodecH264* settings) const {
   if (!codec_settings_set_) {
     return false;
   }
@@ -249,8 +240,7 @@
   return true;
 }
 
-bool FakeVideoSendStream::GetAv1Settings(
-    webrtc::VideoCodecAV1* settings) const {
+bool FakeVideoSendStream::GetAv1Settings(VideoCodecAV1* settings) const {
   if (!codec_settings_set_) {
     return false;
   }
@@ -276,7 +266,7 @@
   return last_frame_->render_time_ms();
 }
 
-void FakeVideoSendStream::OnFrame(const webrtc::VideoFrame& frame) {
+void FakeVideoSendStream::OnFrame(const VideoFrame& frame) {
   ++num_swapped_frames_;
   if (!last_frame_ || frame.width() != last_frame_->width() ||
       frame.height() != last_frame_->height() ||
@@ -288,9 +278,8 @@
               env_.field_trials(), frame.width(), frame.height(),
               encoder_config_);
     } else {
-      webrtc::VideoEncoder::EncoderInfo encoder_info;
-      auto factory =
-          rtc::make_ref_counted<webrtc::EncoderStreamFactory>(encoder_info);
+      VideoEncoder::EncoderInfo encoder_info;
+      auto factory = rtc::make_ref_counted<EncoderStreamFactory>(encoder_info);
 
       video_streams_ = factory->CreateEncoderStreams(
           env_.field_trials(), frame.width(), frame.height(), encoder_config_);
@@ -299,23 +288,21 @@
   last_frame_ = frame;
 }
 
-void FakeVideoSendStream::SetStats(
-    const webrtc::VideoSendStream::Stats& stats) {
+void FakeVideoSendStream::SetStats(const VideoSendStream::Stats& stats) {
   stats_ = stats;
 }
 
-webrtc::VideoSendStream::Stats FakeVideoSendStream::GetStats() {
+VideoSendStream::Stats FakeVideoSendStream::GetStats() {
   return stats_;
 }
 
-void FakeVideoSendStream::ReconfigureVideoEncoder(
-    webrtc::VideoEncoderConfig config) {
+void FakeVideoSendStream::ReconfigureVideoEncoder(VideoEncoderConfig config) {
   ReconfigureVideoEncoder(std::move(config), nullptr);
 }
 
 void FakeVideoSendStream::ReconfigureVideoEncoder(
-    webrtc::VideoEncoderConfig config,
-    webrtc::SetParametersCallback callback) {
+    VideoEncoderConfig config,
+    SetParametersCallback callback) {
   int width, height;
   if (last_frame_) {
     width = last_frame_->width();
@@ -328,9 +315,8 @@
     video_streams_ = config.video_stream_factory->CreateEncoderStreams(
         env_.field_trials(), width, height, config);
   } else {
-    webrtc::VideoEncoder::EncoderInfo encoder_info;
-    auto factory =
-        rtc::make_ref_counted<webrtc::EncoderStreamFactory>(encoder_info);
+    VideoEncoder::EncoderInfo encoder_info;
+    auto factory = rtc::make_ref_counted<EncoderStreamFactory>(encoder_info);
 
     video_streams_ = factory->CreateEncoderStreams(env_.field_trials(), width,
                                                    height, config);
@@ -367,7 +353,7 @@
   codec_settings_set_ = config.encoder_specific_settings != nullptr;
   encoder_config_ = std::move(config);
   ++num_encoder_reconfigurations_;
-  webrtc::InvokeSetParametersCallback(callback, webrtc::RTCError::OK());
+  webrtc::InvokeSetParametersCallback(callback, RTCError::OK());
 }
 
 void FakeVideoSendStream::Start() {
@@ -379,33 +365,33 @@
 }
 
 void FakeVideoSendStream::AddAdaptationResource(
-    rtc::scoped_refptr<webrtc::Resource> /* resource */) {}
+    scoped_refptr<Resource> /* resource */) {}
 
-std::vector<rtc::scoped_refptr<webrtc::Resource>>
+std::vector<scoped_refptr<Resource>>
 FakeVideoSendStream::GetAdaptationResources() {
   return {};
 }
 
 void FakeVideoSendStream::SetSource(
-    rtc::VideoSourceInterface<webrtc::VideoFrame>* source,
-    const webrtc::DegradationPreference& degradation_preference) {
+    rtc::VideoSourceInterface<VideoFrame>* source,
+    const DegradationPreference& degradation_preference) {
   if (source_)
     source_->RemoveSink(this);
   source_ = source;
   switch (degradation_preference) {
-    case webrtc::DegradationPreference::MAINTAIN_FRAMERATE:
+    case DegradationPreference::MAINTAIN_FRAMERATE:
       resolution_scaling_enabled_ = true;
       framerate_scaling_enabled_ = false;
       break;
-    case webrtc::DegradationPreference::MAINTAIN_RESOLUTION:
+    case DegradationPreference::MAINTAIN_RESOLUTION:
       resolution_scaling_enabled_ = false;
       framerate_scaling_enabled_ = true;
       break;
-    case webrtc::DegradationPreference::BALANCED:
+    case DegradationPreference::BALANCED:
       resolution_scaling_enabled_ = true;
       framerate_scaling_enabled_ = true;
       break;
-    case webrtc::DegradationPreference::DISABLED:
+    case DegradationPreference::DISABLED:
       resolution_scaling_enabled_ = false;
       framerate_scaling_enabled_ = false;
       break;
@@ -428,11 +414,11 @@
 }
 
 FakeVideoReceiveStream::FakeVideoReceiveStream(
-    webrtc::VideoReceiveStreamInterface::Config config)
+    VideoReceiveStreamInterface::Config config)
     : config_(std::move(config)), receiving_(false) {}
 
-const webrtc::VideoReceiveStreamInterface::Config&
-FakeVideoReceiveStream::GetConfig() const {
+const VideoReceiveStreamInterface::Config& FakeVideoReceiveStream::GetConfig()
+    const {
   return config_;
 }
 
@@ -440,12 +426,11 @@
   return receiving_;
 }
 
-void FakeVideoReceiveStream::InjectFrame(const webrtc::VideoFrame& frame) {
+void FakeVideoReceiveStream::InjectFrame(const VideoFrame& frame) {
   config_.renderer->OnFrame(frame);
 }
 
-webrtc::VideoReceiveStreamInterface::Stats FakeVideoReceiveStream::GetStats()
-    const {
+VideoReceiveStreamInterface::Stats FakeVideoReceiveStream::GetStats() const {
   return stats_;
 }
 
@@ -458,20 +443,20 @@
 }
 
 void FakeVideoReceiveStream::SetStats(
-    const webrtc::VideoReceiveStreamInterface::Stats& stats) {
+    const VideoReceiveStreamInterface::Stats& stats) {
   stats_ = stats;
 }
 
 FakeFlexfecReceiveStream::FakeFlexfecReceiveStream(
-    const webrtc::FlexfecReceiveStream::Config config)
+    const FlexfecReceiveStream::Config config)
     : config_(std::move(config)) {}
 
-const webrtc::FlexfecReceiveStream::Config&
-FakeFlexfecReceiveStream::GetConfig() const {
+const FlexfecReceiveStream::Config& FakeFlexfecReceiveStream::GetConfig()
+    const {
   return config_;
 }
 
-void FakeFlexfecReceiveStream::OnRtpPacket(const webrtc::RtpPacketReceived&) {
+void FakeFlexfecReceiveStream::OnRtpPacket(const RtpPacketReceived&) {
   RTC_DCHECK_NOTREACHED() << "Not implemented.";
 }
 
@@ -479,8 +464,8 @@
     : FakeCall(env, rtc::Thread::Current(), rtc::Thread::Current()) {}
 
 FakeCall::FakeCall(const Environment& env,
-                   webrtc::TaskQueueBase* worker_thread,
-                   webrtc::TaskQueueBase* network_thread)
+                   TaskQueueBase* worker_thread,
+                   TaskQueueBase* network_thread)
     : env_(env),
       network_thread_(network_thread),
       worker_thread_(worker_thread),
@@ -544,15 +529,15 @@
   return flexfec_receive_streams_;
 }
 
-webrtc::NetworkState FakeCall::GetNetworkState(webrtc::MediaType media) const {
+NetworkState FakeCall::GetNetworkState(MediaType media) const {
   switch (media) {
-    case webrtc::MediaType::AUDIO:
+    case MediaType::AUDIO:
       return audio_network_state_;
-    case webrtc::MediaType::VIDEO:
+    case MediaType::VIDEO:
       return video_network_state_;
-    case webrtc::MediaType::DATA:
-    case webrtc::MediaType::ANY:
-    case webrtc::MediaType::UNSUPPORTED:
+    case MediaType::DATA:
+    case MediaType::ANY:
+    case MediaType::UNSUPPORTED:
       ADD_FAILURE() << "GetNetworkState called with unknown parameter.";
       return webrtc::kNetworkDown;
   }
@@ -563,8 +548,8 @@
   return webrtc::kNetworkDown;
 }
 
-webrtc::AudioSendStream* FakeCall::CreateAudioSendStream(
-    const webrtc::AudioSendStream::Config& config) {
+AudioSendStream* FakeCall::CreateAudioSendStream(
+    const AudioSendStream::Config& config) {
   FakeAudioSendStream* fake_stream =
       new FakeAudioSendStream(next_stream_id_++, config);
   audio_send_streams_.push_back(fake_stream);
@@ -572,7 +557,7 @@
   return fake_stream;
 }
 
-void FakeCall::DestroyAudioSendStream(webrtc::AudioSendStream* send_stream) {
+void FakeCall::DestroyAudioSendStream(AudioSendStream* send_stream) {
   auto it = absl::c_find(audio_send_streams_,
                          static_cast<FakeAudioSendStream*>(send_stream));
   if (it == audio_send_streams_.end()) {
@@ -583,8 +568,8 @@
   }
 }
 
-webrtc::AudioReceiveStreamInterface* FakeCall::CreateAudioReceiveStream(
-    const webrtc::AudioReceiveStreamInterface::Config& config) {
+AudioReceiveStreamInterface* FakeCall::CreateAudioReceiveStream(
+    const AudioReceiveStreamInterface::Config& config) {
   audio_receive_streams_.push_back(
       new FakeAudioReceiveStream(next_stream_id_++, config));
   ++num_created_receive_streams_;
@@ -592,7 +577,7 @@
 }
 
 void FakeCall::DestroyAudioReceiveStream(
-    webrtc::AudioReceiveStreamInterface* receive_stream) {
+    AudioReceiveStreamInterface* receive_stream) {
   auto it = absl::c_find(audio_receive_streams_,
                          static_cast<FakeAudioReceiveStream*>(receive_stream));
   if (it == audio_receive_streams_.end()) {
@@ -603,9 +588,9 @@
   }
 }
 
-webrtc::VideoSendStream* FakeCall::CreateVideoSendStream(
-    webrtc::VideoSendStream::Config config,
-    webrtc::VideoEncoderConfig encoder_config) {
+VideoSendStream* FakeCall::CreateVideoSendStream(
+    VideoSendStream::Config config,
+    VideoEncoderConfig encoder_config) {
   FakeVideoSendStream* fake_stream = new FakeVideoSendStream(
       env_, std::move(config), std::move(encoder_config));
   video_send_streams_.push_back(fake_stream);
@@ -613,7 +598,7 @@
   return fake_stream;
 }
 
-void FakeCall::DestroyVideoSendStream(webrtc::VideoSendStream* send_stream) {
+void FakeCall::DestroyVideoSendStream(VideoSendStream* send_stream) {
   auto it = absl::c_find(video_send_streams_,
                          static_cast<FakeVideoSendStream*>(send_stream));
   if (it == video_send_streams_.end()) {
@@ -624,8 +609,8 @@
   }
 }
 
-webrtc::VideoReceiveStreamInterface* FakeCall::CreateVideoReceiveStream(
-    webrtc::VideoReceiveStreamInterface::Config config) {
+VideoReceiveStreamInterface* FakeCall::CreateVideoReceiveStream(
+    VideoReceiveStreamInterface::Config config) {
   video_receive_streams_.push_back(
       new FakeVideoReceiveStream(std::move(config)));
   ++num_created_receive_streams_;
@@ -633,7 +618,7 @@
 }
 
 void FakeCall::DestroyVideoReceiveStream(
-    webrtc::VideoReceiveStreamInterface* receive_stream) {
+    VideoReceiveStreamInterface* receive_stream) {
   auto it = absl::c_find(video_receive_streams_,
                          static_cast<FakeVideoReceiveStream*>(receive_stream));
   if (it == video_receive_streams_.end()) {
@@ -644,8 +629,8 @@
   }
 }
 
-webrtc::FlexfecReceiveStream* FakeCall::CreateFlexfecReceiveStream(
-    const webrtc::FlexfecReceiveStream::Config config) {
+FlexfecReceiveStream* FakeCall::CreateFlexfecReceiveStream(
+    const FlexfecReceiveStream::Config config) {
   FakeFlexfecReceiveStream* fake_stream =
       new FakeFlexfecReceiveStream(std::move(config));
   flexfec_receive_streams_.push_back(fake_stream);
@@ -654,7 +639,7 @@
 }
 
 void FakeCall::DestroyFlexfecReceiveStream(
-    webrtc::FlexfecReceiveStream* receive_stream) {
+    FlexfecReceiveStream* receive_stream) {
   auto it =
       absl::c_find(flexfec_receive_streams_,
                    static_cast<FakeFlexfecReceiveStream*>(receive_stream));
@@ -667,16 +652,15 @@
   }
 }
 
-void FakeCall::AddAdaptationResource(
-    rtc::scoped_refptr<webrtc::Resource> /* resource */) {}
+void FakeCall::AddAdaptationResource(scoped_refptr<Resource> /* resource */) {}
 
-webrtc::PacketReceiver* FakeCall::Receiver() {
+PacketReceiver* FakeCall::Receiver() {
   return this;
 }
 
 void FakeCall::DeliverRtpPacket(
-    webrtc::MediaType media_type,
-    webrtc::RtpPacketReceived packet,
+    MediaType media_type,
+    RtpPacketReceived packet,
     OnUndemuxablePacketHandler undemuxable_packet_handler) {
   if (!DeliverPacketInternal(media_type, packet.Ssrc(), packet.Buffer(),
                              packet.arrival_time())) {
@@ -688,16 +672,15 @@
   last_received_rtp_packet_ = packet;
 }
 
-bool FakeCall::DeliverPacketInternal(webrtc::MediaType media_type,
+bool FakeCall::DeliverPacketInternal(MediaType media_type,
                                      uint32_t ssrc,
-                                     const rtc::CopyOnWriteBuffer& packet,
-                                     webrtc::Timestamp arrival_time) {
+                                     const CopyOnWriteBuffer& packet,
+                                     Timestamp arrival_time) {
   EXPECT_GE(packet.size(), 12u);
   RTC_DCHECK(arrival_time.IsFinite());
-  RTC_DCHECK(media_type == webrtc::MediaType::AUDIO ||
-             media_type == webrtc::MediaType::VIDEO);
+  RTC_DCHECK(media_type == MediaType::AUDIO || media_type == MediaType::VIDEO);
 
-  if (media_type == webrtc::MediaType::VIDEO) {
+  if (media_type == MediaType::VIDEO) {
     for (auto receiver : video_receive_streams_) {
       if (receiver->GetConfig().rtp.remote_ssrc == ssrc ||
           receiver->GetConfig().rtp.rtx_ssrc == ssrc) {
@@ -706,7 +689,7 @@
       }
     }
   }
-  if (media_type == webrtc::MediaType::AUDIO) {
+  if (media_type == MediaType::AUDIO) {
     for (auto receiver : audio_receive_streams_) {
       if (receiver->GetConfig().rtp.remote_ssrc == ssrc) {
         receiver->DeliverRtp(packet.cdata(), packet.size(), arrival_time.us());
@@ -718,7 +701,7 @@
   return false;
 }
 
-void FakeCall::SetStats(const webrtc::Call::Stats& stats) {
+void FakeCall::SetStats(const Call::Stats& stats) {
   stats_ = stats;
 }
 
@@ -730,30 +713,29 @@
   return num_created_receive_streams_;
 }
 
-webrtc::Call::Stats FakeCall::GetStats() const {
+Call::Stats FakeCall::GetStats() const {
   return stats_;
 }
 
-webrtc::TaskQueueBase* FakeCall::network_thread() const {
+TaskQueueBase* FakeCall::network_thread() const {
   return network_thread_;
 }
 
-webrtc::TaskQueueBase* FakeCall::worker_thread() const {
+TaskQueueBase* FakeCall::worker_thread() const {
   return worker_thread_;
 }
 
-void FakeCall::SignalChannelNetworkState(webrtc::MediaType media,
-                                         webrtc::NetworkState state) {
+void FakeCall::SignalChannelNetworkState(MediaType media, NetworkState state) {
   switch (media) {
-    case webrtc::MediaType::AUDIO:
+    case MediaType::AUDIO:
       audio_network_state_ = state;
       break;
-    case webrtc::MediaType::VIDEO:
+    case MediaType::VIDEO:
       video_network_state_ = state;
       break;
-    case webrtc::MediaType::DATA:
-    case webrtc::MediaType::ANY:
-    case webrtc::MediaType::UNSUPPORTED:
+    case MediaType::DATA:
+    case MediaType::ANY:
+    case MediaType::UNSUPPORTED:
       ADD_FAILURE()
           << "SignalChannelNetworkState called with unknown parameter.";
   }
@@ -762,25 +744,25 @@
 void FakeCall::OnAudioTransportOverheadChanged(
     int /* transport_overhead_per_packet */) {}
 
-void FakeCall::OnLocalSsrcUpdated(webrtc::AudioReceiveStreamInterface& stream,
+void FakeCall::OnLocalSsrcUpdated(AudioReceiveStreamInterface& stream,
                                   uint32_t local_ssrc) {
   auto& fake_stream = static_cast<FakeAudioReceiveStream&>(stream);
   fake_stream.SetLocalSsrc(local_ssrc);
 }
 
-void FakeCall::OnLocalSsrcUpdated(webrtc::VideoReceiveStreamInterface& stream,
+void FakeCall::OnLocalSsrcUpdated(VideoReceiveStreamInterface& stream,
                                   uint32_t local_ssrc) {
   auto& fake_stream = static_cast<FakeVideoReceiveStream&>(stream);
   fake_stream.SetLocalSsrc(local_ssrc);
 }
 
-void FakeCall::OnLocalSsrcUpdated(webrtc::FlexfecReceiveStream& stream,
+void FakeCall::OnLocalSsrcUpdated(FlexfecReceiveStream& stream,
                                   uint32_t local_ssrc) {
   auto& fake_stream = static_cast<FakeFlexfecReceiveStream&>(stream);
   fake_stream.SetLocalSsrc(local_ssrc);
 }
 
-void FakeCall::OnUpdateSyncGroup(webrtc::AudioReceiveStreamInterface& stream,
+void FakeCall::OnUpdateSyncGroup(AudioReceiveStreamInterface& stream,
                                  absl::string_view sync_group) {
   auto& fake_stream = static_cast<FakeAudioReceiveStream&>(stream);
   fake_stream.SetSyncGroup(sync_group);
@@ -793,4 +775,4 @@
   }
 }
 
-}  // namespace cricket
+}  // namespace webrtc
diff --git a/media/engine/fake_webrtc_call.h b/media/engine/fake_webrtc_call.h
index 4e7f68f..983bd4b 100644
--- a/media/engine/fake_webrtc_call.h
+++ b/media/engine/fake_webrtc_call.h
@@ -70,8 +70,8 @@
 #include "test/gmock.h"
 #include "video/config/video_encoder_config.h"
 
-namespace cricket {
-class FakeAudioSendStream final : public webrtc::AudioSendStream {
+namespace webrtc {
+class FakeAudioSendStream final : public AudioSendStream {
  public:
   struct TelephoneEvent {
     int payload_type = -1;
@@ -80,54 +80,50 @@
     int duration_ms = 0;
   };
 
-  explicit FakeAudioSendStream(int id,
-                               const webrtc::AudioSendStream::Config& config);
+  explicit FakeAudioSendStream(int id, const AudioSendStream::Config& config);
 
   int id() const { return id_; }
-  const webrtc::AudioSendStream::Config& GetConfig() const override;
-  void SetStats(const webrtc::AudioSendStream::Stats& stats);
+  const AudioSendStream::Config& GetConfig() const override;
+  void SetStats(const AudioSendStream::Stats& stats);
   TelephoneEvent GetLatestTelephoneEvent() const;
   bool IsSending() const { return sending_; }
   bool muted() const { return muted_; }
 
  private:
   // webrtc::AudioSendStream implementation.
-  void Reconfigure(const webrtc::AudioSendStream::Config& config,
-                   webrtc::SetParametersCallback callback) override;
+  void Reconfigure(const AudioSendStream::Config& config,
+                   SetParametersCallback callback) override;
   void Start() override { sending_ = true; }
   void Stop() override { sending_ = false; }
-  void SendAudioData(
-      std::unique_ptr<webrtc::AudioFrame> /* audio_frame */) override {}
+  void SendAudioData(std::unique_ptr<AudioFrame> /* audio_frame */) override {}
   bool SendTelephoneEvent(int payload_type,
                           int payload_frequency,
                           int event,
                           int duration_ms) override;
   void SetMuted(bool muted) override;
-  webrtc::AudioSendStream::Stats GetStats() const override;
-  webrtc::AudioSendStream::Stats GetStats(
-      bool has_remote_tracks) const override;
+  AudioSendStream::Stats GetStats() const override;
+  AudioSendStream::Stats GetStats(bool has_remote_tracks) const override;
 
   int id_ = -1;
   TelephoneEvent latest_telephone_event_;
-  webrtc::AudioSendStream::Config config_;
-  webrtc::AudioSendStream::Stats stats_;
+  AudioSendStream::Config config_;
+  AudioSendStream::Stats stats_;
   bool sending_ = false;
   bool muted_ = false;
 };
 
-class FakeAudioReceiveStream final
-    : public webrtc::AudioReceiveStreamInterface {
+class FakeAudioReceiveStream final : public AudioReceiveStreamInterface {
  public:
   explicit FakeAudioReceiveStream(
       int id,
-      const webrtc::AudioReceiveStreamInterface::Config& config);
+      const AudioReceiveStreamInterface::Config& config);
 
   int id() const { return id_; }
-  const webrtc::AudioReceiveStreamInterface::Config& GetConfig() const;
-  void SetStats(const webrtc::AudioReceiveStreamInterface::Stats& stats);
+  const AudioReceiveStreamInterface::Config& GetConfig() const;
+  void SetStats(const AudioReceiveStreamInterface::Stats& stats);
   int received_packets() const { return received_packets_; }
   bool VerifyLastPacket(const uint8_t* data, size_t length) const;
-  const webrtc::AudioSinkInterface* sink() const { return sink_; }
+  const AudioSinkInterface* sink() const { return sink_; }
   float gain() const { return gain_; }
   bool DeliverRtp(const uint8_t* packet, size_t length, int64_t packet_time_us);
   bool started() const { return started_; }
@@ -148,19 +144,17 @@
   void Stop() override { started_ = false; }
   bool IsRunning() const override { return started_; }
   void SetDepacketizerToDecoderFrameTransformer(
-      rtc::scoped_refptr<webrtc::FrameTransformerInterface> frame_transformer)
-      override;
-  void SetDecoderMap(
-      std::map<int, webrtc::SdpAudioFormat> decoder_map) override;
+      scoped_refptr<FrameTransformerInterface> frame_transformer) override;
+  void SetDecoderMap(std::map<int, SdpAudioFormat> decoder_map) override;
   void SetNackHistory(int history_ms) override;
-  void SetRtcpMode(webrtc::RtcpMode mode) override;
+  void SetRtcpMode(RtcpMode mode) override;
   void SetNonSenderRttMeasurement(bool enabled) override;
-  void SetFrameDecryptor(rtc::scoped_refptr<webrtc::FrameDecryptorInterface>
-                             frame_decryptor) override;
+  void SetFrameDecryptor(
+      scoped_refptr<FrameDecryptorInterface> frame_decryptor) override;
 
-  webrtc::AudioReceiveStreamInterface::Stats GetStats(
+  AudioReceiveStreamInterface::Stats GetStats(
       bool get_and_clear_legacy_stats) const override;
-  void SetSink(webrtc::AudioSinkInterface* sink) override;
+  void SetSink(AudioSinkInterface* sink) override;
   void SetGain(float gain) override;
   bool SetBaseMinimumPlayoutDelayMs(int delay_ms) override {
     base_mininum_playout_delay_ms_ = delay_ms;
@@ -169,49 +163,48 @@
   int GetBaseMinimumPlayoutDelayMs() const override {
     return base_mininum_playout_delay_ms_;
   }
-  std::vector<webrtc::RtpSource> GetSources() const override {
-    return std::vector<webrtc::RtpSource>();
+  std::vector<RtpSource> GetSources() const override {
+    return std::vector<RtpSource>();
   }
-  webrtc::AudioMixer::Source* source() override {
+  AudioMixer::Source* source() override {
     // TODO(b/397376626): Add a Fake AudioMixer::Source
     return nullptr;
   }
 
  private:
   int id_ = -1;
-  webrtc::AudioReceiveStreamInterface::Config config_;
-  webrtc::AudioReceiveStreamInterface::Stats stats_;
+  AudioReceiveStreamInterface::Config config_;
+  AudioReceiveStreamInterface::Stats stats_;
   int received_packets_ = 0;
-  webrtc::AudioSinkInterface* sink_ = nullptr;
+  AudioSinkInterface* sink_ = nullptr;
   float gain_ = 1.0f;
-  rtc::Buffer last_packet_;
+  Buffer last_packet_;
   bool started_ = false;
   int base_mininum_playout_delay_ms_ = 0;
 };
 
-class FakeVideoSendStream final
-    : public webrtc::VideoSendStream,
-      public rtc::VideoSinkInterface<webrtc::VideoFrame> {
+class FakeVideoSendStream final : public VideoSendStream,
+                                  public rtc::VideoSinkInterface<VideoFrame> {
  public:
-  FakeVideoSendStream(const webrtc::Environment& env,
-                      webrtc::VideoSendStream::Config config,
-                      webrtc::VideoEncoderConfig encoder_config);
+  FakeVideoSendStream(const Environment& env,
+                      VideoSendStream::Config config,
+                      VideoEncoderConfig encoder_config);
   ~FakeVideoSendStream() override;
-  const webrtc::VideoSendStream::Config& GetConfig() const;
-  const webrtc::VideoEncoderConfig& GetEncoderConfig() const;
-  const std::vector<webrtc::VideoStream>& GetVideoStreams() const;
+  const VideoSendStream::Config& GetConfig() const;
+  const VideoEncoderConfig& GetEncoderConfig() const;
+  const std::vector<VideoStream>& GetVideoStreams() const;
 
   bool IsSending() const;
-  bool GetVp8Settings(webrtc::VideoCodecVP8* settings) const;
-  bool GetVp9Settings(webrtc::VideoCodecVP9* settings) const;
-  bool GetH264Settings(webrtc::VideoCodecH264* settings) const;
-  bool GetAv1Settings(webrtc::VideoCodecAV1* settings) const;
+  bool GetVp8Settings(VideoCodecVP8* settings) const;
+  bool GetVp9Settings(VideoCodecVP9* settings) const;
+  bool GetH264Settings(VideoCodecH264* settings) const;
+  bool GetAv1Settings(VideoCodecAV1* settings) const;
 
   int GetNumberOfSwappedFrames() const;
   int GetLastWidth() const;
   int GetLastHeight() const;
   int64_t GetLastTimestamp() const;
-  void SetStats(const webrtc::VideoSendStream::Stats& stats);
+  void SetStats(const VideoSendStream::Stats& stats);
   int num_encoder_reconfigurations() const {
     return num_encoder_reconfigurations_;
   }
@@ -222,9 +215,7 @@
   bool framerate_scaling_enabled() const { return framerate_scaling_enabled_; }
   void InjectVideoSinkWants(const rtc::VideoSinkWants& wants);
 
-  rtc::VideoSourceInterface<webrtc::VideoFrame>* source() const {
-    return source_;
-  }
+  rtc::VideoSourceInterface<VideoFrame>* source() const { return source_; }
   void GenerateKeyFrame(const std::vector<std::string>& rids);
   const std::vector<std::string>& GetKeyFramesRequested() const {
     return keyframes_requested_by_rid_;
@@ -232,65 +223,60 @@
 
  private:
   // rtc::VideoSinkInterface<VideoFrame> implementation.
-  void OnFrame(const webrtc::VideoFrame& frame) override;
+  void OnFrame(const VideoFrame& frame) override;
 
   // webrtc::VideoSendStream implementation.
   void Start() override;
   void Stop() override;
   bool started() override { return IsSending(); }
-  void AddAdaptationResource(
-      rtc::scoped_refptr<webrtc::Resource> resource) override;
-  std::vector<rtc::scoped_refptr<webrtc::Resource>> GetAdaptationResources()
-      override;
-  void SetSource(
-      rtc::VideoSourceInterface<webrtc::VideoFrame>* source,
-      const webrtc::DegradationPreference& degradation_preference) override;
-  webrtc::VideoSendStream::Stats GetStats() override;
+  void AddAdaptationResource(scoped_refptr<Resource> resource) override;
+  std::vector<scoped_refptr<Resource>> GetAdaptationResources() override;
+  void SetSource(rtc::VideoSourceInterface<VideoFrame>* source,
+                 const DegradationPreference& degradation_preference) override;
+  VideoSendStream::Stats GetStats() override;
 
-  void ReconfigureVideoEncoder(webrtc::VideoEncoderConfig config) override;
-  void ReconfigureVideoEncoder(webrtc::VideoEncoderConfig config,
-                               webrtc::SetParametersCallback callback) override;
+  void ReconfigureVideoEncoder(VideoEncoderConfig config) override;
+  void ReconfigureVideoEncoder(VideoEncoderConfig config,
+                               SetParametersCallback callback) override;
 
-  const webrtc::Environment env_;
+  const Environment env_;
   bool sending_;
-  webrtc::VideoSendStream::Config config_;
-  webrtc::VideoEncoderConfig encoder_config_;
-  std::vector<webrtc::VideoStream> video_streams_;
+  VideoSendStream::Config config_;
+  VideoEncoderConfig encoder_config_;
+  std::vector<VideoStream> video_streams_;
   rtc::VideoSinkWants sink_wants_;
 
   bool codec_settings_set_;
   union CodecSpecificSettings {
-    webrtc::VideoCodecVP8 vp8;
-    webrtc::VideoCodecVP9 vp9;
-    webrtc::VideoCodecH264 h264;
-    webrtc::VideoCodecAV1 av1;
+    VideoCodecVP8 vp8;
+    VideoCodecVP9 vp9;
+    VideoCodecH264 h264;
+    VideoCodecAV1 av1;
   } codec_specific_settings_;
   bool resolution_scaling_enabled_;
   bool framerate_scaling_enabled_;
-  rtc::VideoSourceInterface<webrtc::VideoFrame>* source_;
+  rtc::VideoSourceInterface<VideoFrame>* source_;
   int num_swapped_frames_;
-  std::optional<webrtc::VideoFrame> last_frame_;
-  webrtc::VideoSendStream::Stats stats_;
+  std::optional<VideoFrame> last_frame_;
+  VideoSendStream::Stats stats_;
   int num_encoder_reconfigurations_ = 0;
   std::vector<std::string> keyframes_requested_by_rid_;
 };
 
-class FakeVideoReceiveStream final
-    : public webrtc::VideoReceiveStreamInterface {
+class FakeVideoReceiveStream final : public VideoReceiveStreamInterface {
  public:
-  explicit FakeVideoReceiveStream(
-      webrtc::VideoReceiveStreamInterface::Config config);
+  explicit FakeVideoReceiveStream(VideoReceiveStreamInterface::Config config);
 
-  const webrtc::VideoReceiveStreamInterface::Config& GetConfig() const;
+  const VideoReceiveStreamInterface::Config& GetConfig() const;
 
   bool IsReceiving() const;
 
-  void InjectFrame(const webrtc::VideoFrame& frame);
+  void InjectFrame(const VideoFrame& frame);
 
-  void SetStats(const webrtc::VideoReceiveStreamInterface::Stats& stats);
+  void SetStats(const VideoReceiveStreamInterface::Stats& stats);
 
-  std::vector<webrtc::RtpSource> GetSources() const override {
-    return std::vector<webrtc::RtpSource>();
+  std::vector<RtpSource> GetSources() const override {
+    return std::vector<RtpSource>();
   }
 
   int base_mininum_playout_delay_ms() const {
@@ -303,13 +289,12 @@
 
   void UpdateRtxSsrc(uint32_t ssrc) { config_.rtp.rtx_ssrc = ssrc; }
 
-  void SetFrameDecryptor(rtc::scoped_refptr<webrtc::FrameDecryptorInterface>
+  void SetFrameDecryptor(scoped_refptr<FrameDecryptorInterface>
                          /* frame_decryptor */) override {}
 
   void SetDepacketizerToDecoderFrameTransformer(
-      rtc::scoped_refptr<
-          webrtc::FrameTransformerInterface> /* frame_transformer */) override {
-  }
+      scoped_refptr<FrameTransformerInterface> /* frame_transformer */)
+      override {}
 
   RecordingState SetAndGetRecordingState(
       RecordingState /* state */,
@@ -318,11 +303,9 @@
   }
   void GenerateKeyFrame() override {}
 
-  void SetRtcpMode(webrtc::RtcpMode mode) override {
-    config_.rtp.rtcp_mode = mode;
-  }
+  void SetRtcpMode(RtcpMode mode) override { config_.rtp.rtcp_mode = mode; }
 
-  void SetFlexFecProtection(webrtc::RtpPacketSinkInterface* sink) override {
+  void SetFlexFecProtection(RtpPacketSinkInterface* sink) override {
     config_.rtp.packet_sink_ = sink;
     config_.rtp.protected_by_flexfec = (sink != nullptr);
   }
@@ -331,7 +314,7 @@
     config_.rtp.lntf.enabled = enabled;
   }
 
-  void SetNackHistory(webrtc::TimeDelta history) override {
+  void SetNackHistory(TimeDelta history) override {
     config_.rtp.nack.rtp_history_ms = history.ms();
   }
 
@@ -353,7 +336,7 @@
   void Start() override;
   void Stop() override;
 
-  webrtc::VideoReceiveStreamInterface::Stats GetStats() const override;
+  VideoReceiveStreamInterface::Stats GetStats() const override;
 
   bool SetBaseMinimumPlayoutDelayMs(int delay_ms) override {
     base_mininum_playout_delay_ms_ = delay_ms;
@@ -365,54 +348,51 @@
   }
 
  private:
-  webrtc::VideoReceiveStreamInterface::Config config_;
+  VideoReceiveStreamInterface::Config config_;
   bool receiving_;
-  webrtc::VideoReceiveStreamInterface::Stats stats_;
+  VideoReceiveStreamInterface::Stats stats_;
 
   int base_mininum_playout_delay_ms_ = 0;
 };
 
-class FakeFlexfecReceiveStream final : public webrtc::FlexfecReceiveStream {
+class FakeFlexfecReceiveStream final : public FlexfecReceiveStream {
  public:
-  explicit FakeFlexfecReceiveStream(
-      const webrtc::FlexfecReceiveStream::Config config);
+  explicit FakeFlexfecReceiveStream(const FlexfecReceiveStream::Config config);
 
   void SetLocalSsrc(uint32_t local_ssrc) {
     config_.rtp.local_ssrc = local_ssrc;
   }
 
-  void SetRtcpMode(webrtc::RtcpMode mode) override { config_.rtcp_mode = mode; }
+  void SetRtcpMode(RtcpMode mode) override { config_.rtcp_mode = mode; }
 
   int payload_type() const override { return config_.payload_type; }
   void SetPayloadType(int payload_type) override {
     config_.payload_type = payload_type;
   }
 
-  const webrtc::FlexfecReceiveStream::Config& GetConfig() const;
+  const FlexfecReceiveStream::Config& GetConfig() const;
 
   uint32_t remote_ssrc() const { return config_.rtp.remote_ssrc; }
 
-  const webrtc::ReceiveStatistics* GetStats() const override { return nullptr; }
+  const ReceiveStatistics* GetStats() const override { return nullptr; }
 
  private:
-  void OnRtpPacket(const webrtc::RtpPacketReceived& packet) override;
+  void OnRtpPacket(const RtpPacketReceived& packet) override;
 
-  webrtc::FlexfecReceiveStream::Config config_;
+  FlexfecReceiveStream::Config config_;
 };
 
-class FakeCall final : public webrtc::Call, public webrtc::PacketReceiver {
+class FakeCall final : public Call, public PacketReceiver {
  public:
-  explicit FakeCall(const webrtc::Environment& env);
-  FakeCall(const webrtc::Environment& env,
-           webrtc::TaskQueueBase* worker_thread,
-           webrtc::TaskQueueBase* network_thread);
+  explicit FakeCall(const Environment& env);
+  FakeCall(const Environment& env,
+           TaskQueueBase* worker_thread,
+           TaskQueueBase* network_thread);
   ~FakeCall() override;
 
-  webrtc::PayloadTypeSuggester* GetPayloadTypeSuggester() {
-    return &pt_suggester_;
-  }
+  PayloadTypeSuggester* GetPayloadTypeSuggester() { return &pt_suggester_; }
 
-  webrtc::MockRtpTransportControllerSend* GetMockTransportControllerSend() {
+  MockRtpTransportControllerSend* GetMockTransportControllerSend() {
     return &transport_controller_send_;
   }
 
@@ -428,7 +408,7 @@
   const std::vector<FakeFlexfecReceiveStream*>& GetFlexfecReceiveStreams();
 
   rtc::SentPacket last_sent_packet() const { return last_sent_packet_; }
-  const webrtc::RtpPacketReceived& last_received_rtp_packet() const {
+  const RtpPacketReceived& last_received_rtp_packet() const {
     return last_received_rtp_packet_;
   }
   size_t GetDeliveredPacketsForSsrc(uint32_t ssrc) const {
@@ -442,100 +422,95 @@
     return last_sent_nonnegative_packet_id_;
   }
 
-  webrtc::NetworkState GetNetworkState(webrtc::MediaType media) const;
+  NetworkState GetNetworkState(MediaType media) const;
   int GetNumCreatedSendStreams() const;
   int GetNumCreatedReceiveStreams() const;
-  void SetStats(const webrtc::Call::Stats& stats);
+  void SetStats(const Call::Stats& stats);
 
   void SetClientBitratePreferences(
-      const webrtc::BitrateSettings& /* preferences */) override {}
-  const webrtc::FieldTrialsView& trials() const override {
-    return env_.field_trials();
-  }
+      const BitrateSettings& /* preferences */) override {}
+  const FieldTrialsView& trials() const override { return env_.field_trials(); }
   void EnableSendCongestionControlFeedbackAccordingToRfc8888() override {}
   int FeedbackAccordingToRfc8888Count() { return 0; }
   int FeedbackAccordingToTransportCcCount() { return 0; }
 
  private:
-  webrtc::AudioSendStream* CreateAudioSendStream(
-      const webrtc::AudioSendStream::Config& config) override;
-  void DestroyAudioSendStream(webrtc::AudioSendStream* send_stream) override;
+  AudioSendStream* CreateAudioSendStream(
+      const AudioSendStream::Config& config) override;
+  void DestroyAudioSendStream(AudioSendStream* send_stream) override;
 
-  webrtc::AudioReceiveStreamInterface* CreateAudioReceiveStream(
-      const webrtc::AudioReceiveStreamInterface::Config& config) override;
+  AudioReceiveStreamInterface* CreateAudioReceiveStream(
+      const AudioReceiveStreamInterface::Config& config) override;
   void DestroyAudioReceiveStream(
-      webrtc::AudioReceiveStreamInterface* receive_stream) override;
+      AudioReceiveStreamInterface* receive_stream) override;
 
-  webrtc::VideoSendStream* CreateVideoSendStream(
-      webrtc::VideoSendStream::Config config,
-      webrtc::VideoEncoderConfig encoder_config) override;
-  void DestroyVideoSendStream(webrtc::VideoSendStream* send_stream) override;
+  VideoSendStream* CreateVideoSendStream(
+      VideoSendStream::Config config,
+      VideoEncoderConfig encoder_config) override;
+  void DestroyVideoSendStream(VideoSendStream* send_stream) override;
 
-  webrtc::VideoReceiveStreamInterface* CreateVideoReceiveStream(
-      webrtc::VideoReceiveStreamInterface::Config config) override;
+  VideoReceiveStreamInterface* CreateVideoReceiveStream(
+      VideoReceiveStreamInterface::Config config) override;
   void DestroyVideoReceiveStream(
-      webrtc::VideoReceiveStreamInterface* receive_stream) override;
+      VideoReceiveStreamInterface* receive_stream) override;
 
-  webrtc::FlexfecReceiveStream* CreateFlexfecReceiveStream(
-      const webrtc::FlexfecReceiveStream::Config config) override;
+  FlexfecReceiveStream* CreateFlexfecReceiveStream(
+      const FlexfecReceiveStream::Config config) override;
   void DestroyFlexfecReceiveStream(
-      webrtc::FlexfecReceiveStream* receive_stream) override;
+      FlexfecReceiveStream* receive_stream) override;
 
-  void AddAdaptationResource(
-      rtc::scoped_refptr<webrtc::Resource> resource) override;
+  void AddAdaptationResource(scoped_refptr<Resource> resource) override;
 
-  webrtc::PacketReceiver* Receiver() override;
+  PacketReceiver* Receiver() override;
 
-  void DeliverRtcpPacket(rtc::CopyOnWriteBuffer /* packet */) override {}
+  void DeliverRtcpPacket(CopyOnWriteBuffer /* packet */) override {}
 
   void DeliverRtpPacket(
-      webrtc::MediaType media_type,
-      webrtc::RtpPacketReceived packet,
+      MediaType media_type,
+      RtpPacketReceived packet,
       OnUndemuxablePacketHandler un_demuxable_packet_handler) override;
 
-  bool DeliverPacketInternal(webrtc::MediaType media_type,
+  bool DeliverPacketInternal(MediaType media_type,
                              uint32_t ssrc,
-                             const rtc::CopyOnWriteBuffer& packet,
-                             webrtc::Timestamp arrival_time);
+                             const CopyOnWriteBuffer& packet,
+                             Timestamp arrival_time);
 
-  webrtc::RtpTransportControllerSendInterface* GetTransportControllerSend()
-      override {
+  RtpTransportControllerSendInterface* GetTransportControllerSend() override {
     return &transport_controller_send_;
   }
 
-  webrtc::Call::Stats GetStats() const override;
+  Call::Stats GetStats() const override;
 
-  webrtc::TaskQueueBase* network_thread() const override;
-  webrtc::TaskQueueBase* worker_thread() const override;
+  TaskQueueBase* network_thread() const override;
+  TaskQueueBase* worker_thread() const override;
 
-  void SignalChannelNetworkState(webrtc::MediaType media,
-                                 webrtc::NetworkState state) override;
+  void SignalChannelNetworkState(MediaType media, NetworkState state) override;
   void OnAudioTransportOverheadChanged(
       int transport_overhead_per_packet) override;
-  void OnLocalSsrcUpdated(webrtc::AudioReceiveStreamInterface& stream,
+  void OnLocalSsrcUpdated(AudioReceiveStreamInterface& stream,
                           uint32_t local_ssrc) override;
-  void OnLocalSsrcUpdated(webrtc::VideoReceiveStreamInterface& stream,
+  void OnLocalSsrcUpdated(VideoReceiveStreamInterface& stream,
                           uint32_t local_ssrc) override;
-  void OnLocalSsrcUpdated(webrtc::FlexfecReceiveStream& stream,
+  void OnLocalSsrcUpdated(FlexfecReceiveStream& stream,
                           uint32_t local_ssrc) override;
-  void OnUpdateSyncGroup(webrtc::AudioReceiveStreamInterface& stream,
+  void OnUpdateSyncGroup(AudioReceiveStreamInterface& stream,
                          absl::string_view sync_group) override;
   void OnSentPacket(const rtc::SentPacket& sent_packet) override;
 
-  const webrtc::Environment env_;
-  webrtc::TaskQueueBase* const network_thread_;
-  webrtc::TaskQueueBase* const worker_thread_;
+  const Environment env_;
+  TaskQueueBase* const network_thread_;
+  TaskQueueBase* const worker_thread_;
 
-  ::testing::NiceMock<webrtc::MockRtpTransportControllerSend>
+  ::testing::NiceMock<MockRtpTransportControllerSend>
       transport_controller_send_;
 
-  webrtc::NetworkState audio_network_state_;
-  webrtc::NetworkState video_network_state_;
+  NetworkState audio_network_state_;
+  NetworkState video_network_state_;
   rtc::SentPacket last_sent_packet_;
-  webrtc::RtpPacketReceived last_received_rtp_packet_;
+  RtpPacketReceived last_received_rtp_packet_;
   int last_sent_nonnegative_packet_id_ = -1;
   int next_stream_id_ = 665;
-  webrtc::Call::Stats stats_;
+  Call::Stats stats_;
   std::vector<FakeVideoSendStream*> video_send_streams_;
   std::vector<FakeAudioSendStream*> audio_send_streams_;
   std::vector<FakeVideoReceiveStream*> video_receive_streams_;
@@ -546,8 +521,19 @@
   int num_created_send_streams_;
   int num_created_receive_streams_;
 
-  webrtc::FakePayloadTypeSuggester pt_suggester_;
+  FakePayloadTypeSuggester pt_suggester_;
 };
 
+}  //  namespace webrtc
+
+// Re-export symbols from the webrtc namespace for backwards compatibility.
+// TODO(bugs.webrtc.org/4222596): Remove once all references are updated.
+namespace cricket {
+using ::webrtc::FakeAudioReceiveStream;
+using ::webrtc::FakeAudioSendStream;
+using ::webrtc::FakeCall;
+using ::webrtc::FakeFlexfecReceiveStream;
+using ::webrtc::FakeVideoReceiveStream;
+using ::webrtc::FakeVideoSendStream;
 }  // namespace cricket
 #endif  // MEDIA_ENGINE_FAKE_WEBRTC_CALL_H_
diff --git a/media/engine/fake_webrtc_video_engine.cc b/media/engine/fake_webrtc_video_engine.cc
index 0fa87f5..8344639 100644
--- a/media/engine/fake_webrtc_video_engine.cc
+++ b/media/engine/fake_webrtc_video_engine.cc
@@ -22,18 +22,16 @@
 #include "rtc_base/logging.h"
 #include "rtc_base/time_utils.h"
 
-namespace cricket {
+namespace webrtc {
 
 namespace {
 
 using ::webrtc::Environment;
 
-static constexpr webrtc::TimeDelta kEventTimeout =
-    webrtc::TimeDelta::Seconds(10);
+static constexpr TimeDelta kEventTimeout = TimeDelta::Seconds(10);
 
-bool IsScalabilityModeSupported(
-    const std::vector<webrtc::SdpVideoFormat>& formats,
-    std::optional<std::string> scalability_mode) {
+bool IsScalabilityModeSupported(const std::vector<SdpVideoFormat>& formats,
+                                std::optional<std::string> scalability_mode) {
   if (!scalability_mode.has_value()) {
     return true;
   }
@@ -63,13 +61,13 @@
   return true;
 }
 
-int32_t FakeWebRtcVideoDecoder::Decode(const webrtc::EncodedImage&, int64_t) {
+int32_t FakeWebRtcVideoDecoder::Decode(const EncodedImage&, int64_t) {
   num_frames_received_++;
   return WEBRTC_VIDEO_CODEC_OK;
 }
 
 int32_t FakeWebRtcVideoDecoder::RegisterDecodeCompleteCallback(
-    webrtc::DecodedImageCallback*) {
+    DecodedImageCallback*) {
   return WEBRTC_VIDEO_CODEC_OK;
 }
 
@@ -85,9 +83,9 @@
 FakeWebRtcVideoDecoderFactory::FakeWebRtcVideoDecoderFactory()
     : num_created_decoders_(0) {}
 
-std::vector<webrtc::SdpVideoFormat>
-FakeWebRtcVideoDecoderFactory::GetSupportedFormats() const {
-  std::vector<webrtc::SdpVideoFormat> formats;
+std::vector<SdpVideoFormat> FakeWebRtcVideoDecoderFactory::GetSupportedFormats()
+    const {
+  std::vector<SdpVideoFormat> formats;
 
   for (const webrtc::SdpVideoFormat& format : supported_codec_formats_) {
     // We need to test erroneous scenarios, so just warn if there's
@@ -102,9 +100,9 @@
   return formats;
 }
 
-std::unique_ptr<webrtc::VideoDecoder> FakeWebRtcVideoDecoderFactory::Create(
-    const webrtc::Environment& /* env */,
-    const webrtc::SdpVideoFormat& format) {
+std::unique_ptr<VideoDecoder> FakeWebRtcVideoDecoderFactory::Create(
+    const Environment& /* env */,
+    const SdpVideoFormat& format) {
   if (format.IsCodecInList(supported_codec_formats_)) {
     num_created_decoders_++;
     std::unique_ptr<FakeWebRtcVideoDecoder> decoder =
@@ -123,7 +121,7 @@
 }
 
 void FakeWebRtcVideoDecoderFactory::AddSupportedVideoCodec(
-    const webrtc::SdpVideoFormat& format) {
+    const SdpVideoFormat& format) {
   supported_codec_formats_.push_back(format);
 }
 
@@ -132,7 +130,7 @@
   // This is to match the default H264 params of cricket::Codec.
   cricket::Codec video_codec = cricket::CreateVideoCodec(name);
   supported_codec_formats_.push_back(
-      webrtc::SdpVideoFormat(video_codec.name, video_codec.params));
+      SdpVideoFormat(video_codec.name, video_codec.params));
 }
 
 int FakeWebRtcVideoDecoderFactory::GetNumCreatedDecoders() {
@@ -156,30 +154,30 @@
 }
 
 void FakeWebRtcVideoEncoder::SetFecControllerOverride(
-    webrtc::FecControllerOverride* /* fec_controller_override */) {
+    FecControllerOverride* /* fec_controller_override */) {
   // Ignored.
 }
 
 int32_t FakeWebRtcVideoEncoder::InitEncode(
-    const webrtc::VideoCodec* codecSettings,
+    const VideoCodec* codecSettings,
     const VideoEncoder::Settings& /* settings */) {
-  webrtc::MutexLock lock(&mutex_);
+  MutexLock lock(&mutex_);
   codec_settings_ = *codecSettings;
   init_encode_event_.Set();
   return WEBRTC_VIDEO_CODEC_OK;
 }
 
 int32_t FakeWebRtcVideoEncoder::Encode(
-    const webrtc::VideoFrame& /* inputImage */,
-    const std::vector<webrtc::VideoFrameType>* /* frame_types */) {
-  webrtc::MutexLock lock(&mutex_);
+    const VideoFrame& /* inputImage */,
+    const std::vector<VideoFrameType>* /* frame_types */) {
+  MutexLock lock(&mutex_);
   ++num_frames_encoded_;
   init_encode_event_.Set();
   return WEBRTC_VIDEO_CODEC_OK;
 }
 
 int32_t FakeWebRtcVideoEncoder::RegisterEncodeCompleteCallback(
-    webrtc::EncodedImageCallback* /* callback */) {
+    EncodedImageCallback* /* callback */) {
   return WEBRTC_VIDEO_CODEC_OK;
 }
 
@@ -190,8 +188,7 @@
 void FakeWebRtcVideoEncoder::SetRates(
     const RateControlParameters& /* parameters */) {}
 
-webrtc::VideoEncoder::EncoderInfo FakeWebRtcVideoEncoder::GetEncoderInfo()
-    const {
+VideoEncoder::EncoderInfo FakeWebRtcVideoEncoder::GetEncoderInfo() const {
   EncoderInfo info;
   info.is_hardware_accelerated = true;
   return info;
@@ -201,13 +198,13 @@
   return init_encode_event_.Wait(kEventTimeout);
 }
 
-webrtc::VideoCodec FakeWebRtcVideoEncoder::GetCodecSettings() {
-  webrtc::MutexLock lock(&mutex_);
+VideoCodec FakeWebRtcVideoEncoder::GetCodecSettings() {
+  MutexLock lock(&mutex_);
   return codec_settings_;
 }
 
 int FakeWebRtcVideoEncoder::GetNumEncodedFrames() {
-  webrtc::MutexLock lock(&mutex_);
+  MutexLock lock(&mutex_);
   return num_frames_encoded_;
 }
 
@@ -215,9 +212,9 @@
 FakeWebRtcVideoEncoderFactory::FakeWebRtcVideoEncoderFactory()
     : num_created_encoders_(0), vp8_factory_mode_(false) {}
 
-std::vector<webrtc::SdpVideoFormat>
-FakeWebRtcVideoEncoderFactory::GetSupportedFormats() const {
-  std::vector<webrtc::SdpVideoFormat> formats;
+std::vector<SdpVideoFormat> FakeWebRtcVideoEncoderFactory::GetSupportedFormats()
+    const {
+  std::vector<SdpVideoFormat> formats;
 
   for (const webrtc::SdpVideoFormat& format : formats_) {
     // Don't add same codec twice.
@@ -228,11 +225,11 @@
   return formats;
 }
 
-webrtc::VideoEncoderFactory::CodecSupport
+VideoEncoderFactory::CodecSupport
 FakeWebRtcVideoEncoderFactory::QueryCodecSupport(
-    const webrtc::SdpVideoFormat& format,
+    const SdpVideoFormat& format,
     std::optional<std::string> scalability_mode) const {
-  std::vector<webrtc::SdpVideoFormat> supported_formats;
+  std::vector<SdpVideoFormat> supported_formats;
   for (const auto& f : formats_) {
     if (format.IsSameCodec(f))
       supported_formats.push_back(f);
@@ -244,19 +241,19 @@
   return {.is_supported = false};
 }
 
-std::unique_ptr<webrtc::VideoEncoder> FakeWebRtcVideoEncoderFactory::Create(
+std::unique_ptr<VideoEncoder> FakeWebRtcVideoEncoderFactory::Create(
     const Environment& env,
-    const webrtc::SdpVideoFormat& format) {
-  webrtc::MutexLock lock(&mutex_);
-  std::unique_ptr<webrtc::VideoEncoder> encoder;
+    const SdpVideoFormat& format) {
+  MutexLock lock(&mutex_);
+  std::unique_ptr<VideoEncoder> encoder;
   if (format.IsCodecInList(formats_)) {
-    if (absl::EqualsIgnoreCase(format.name, kVp8CodecName) &&
+    if (absl::EqualsIgnoreCase(format.name, cricket::kVp8CodecName) &&
         !vp8_factory_mode_) {
       // The simulcast adapter will ask this factory for multiple VP8
       // encoders. Enter vp8_factory_mode so that we now create these encoders
       // instead of more adapters.
       vp8_factory_mode_ = true;
-      encoder = std::make_unique<webrtc::SimulcastEncoderAdapter>(
+      encoder = std::make_unique<SimulcastEncoderAdapter>(
           env, /*primary_factory=*/this, /*fallback_factory=*/nullptr, format);
     } else {
       num_created_encoders_++;
@@ -276,42 +273,42 @@
     if (GetNumCreatedEncoders() >= num_encoders)
       return true;
     wait_time = kEventTimeout.ms() - (rtc::TimeMillis() - start_offset_ms);
-  } while (wait_time > 0 && created_video_encoder_event_.Wait(
-                                webrtc::TimeDelta::Millis(wait_time)));
+  } while (wait_time > 0 &&
+           created_video_encoder_event_.Wait(TimeDelta::Millis(wait_time)));
   return false;
 }
 
 void FakeWebRtcVideoEncoderFactory::EncoderDestroyed(
     FakeWebRtcVideoEncoder* encoder) {
-  webrtc::MutexLock lock(&mutex_);
+  MutexLock lock(&mutex_);
   encoders_.erase(std::remove(encoders_.begin(), encoders_.end(), encoder),
                   encoders_.end());
 }
 
 void FakeWebRtcVideoEncoderFactory::AddSupportedVideoCodec(
-    const webrtc::SdpVideoFormat& format) {
+    const SdpVideoFormat& format) {
   formats_.push_back(format);
 }
 
 void FakeWebRtcVideoEncoderFactory::AddSupportedVideoCodecType(
     const std::string& name,
-    const std::vector<webrtc::ScalabilityMode>& scalability_modes) {
+    const std::vector<ScalabilityMode>& scalability_modes) {
   // This is to match the default H264 params of cricket::Codec.
   cricket::Codec video_codec = cricket::CreateVideoCodec(name);
-  formats_.push_back(webrtc::SdpVideoFormat(
-      video_codec.name, video_codec.params,
-      {scalability_modes.begin(), scalability_modes.end()}));
+  formats_.push_back(
+      SdpVideoFormat(video_codec.name, video_codec.params,
+                     {scalability_modes.begin(), scalability_modes.end()}));
 }
 
 int FakeWebRtcVideoEncoderFactory::GetNumCreatedEncoders() {
-  webrtc::MutexLock lock(&mutex_);
+  MutexLock lock(&mutex_);
   return num_created_encoders_;
 }
 
 const std::vector<FakeWebRtcVideoEncoder*>
 FakeWebRtcVideoEncoderFactory::encoders() {
-  webrtc::MutexLock lock(&mutex_);
+  MutexLock lock(&mutex_);
   return encoders_;
 }
 
-}  // namespace cricket
+}  // namespace webrtc
diff --git a/media/engine/fake_webrtc_video_engine.h b/media/engine/fake_webrtc_video_engine.h
index 8d78e86..6fa4edc 100644
--- a/media/engine/fake_webrtc_video_engine.h
+++ b/media/engine/fake_webrtc_video_engine.h
@@ -34,21 +34,20 @@
 #include "rtc_base/synchronization/mutex.h"
 #include "rtc_base/thread_annotations.h"
 
-namespace cricket {
+namespace webrtc {
 
 class FakeWebRtcVideoDecoderFactory;
 class FakeWebRtcVideoEncoderFactory;
 
 // Fake class for mocking out webrtc::VideoDecoder
-class FakeWebRtcVideoDecoder : public webrtc::VideoDecoder {
+class FakeWebRtcVideoDecoder : public VideoDecoder {
  public:
   explicit FakeWebRtcVideoDecoder(FakeWebRtcVideoDecoderFactory* factory);
   ~FakeWebRtcVideoDecoder();
 
   bool Configure(const Settings& settings) override;
-  int32_t Decode(const webrtc::EncodedImage&, int64_t) override;
-  int32_t RegisterDecodeCompleteCallback(
-      webrtc::DecodedImageCallback*) override;
+  int32_t Decode(const EncodedImage&, int64_t) override;
+  int32_t RegisterDecodeCompleteCallback(DecodedImageCallback*) override;
   int32_t Release() override;
 
   int GetNumFramesReceived() const;
@@ -59,90 +58,96 @@
 };
 
 // Fake class for mocking out webrtc::VideoDecoderFactory.
-class FakeWebRtcVideoDecoderFactory : public webrtc::VideoDecoderFactory {
+class FakeWebRtcVideoDecoderFactory : public VideoDecoderFactory {
  public:
   FakeWebRtcVideoDecoderFactory();
 
-  std::vector<webrtc::SdpVideoFormat> GetSupportedFormats() const override;
-  std::unique_ptr<webrtc::VideoDecoder> Create(
-      const webrtc::Environment& env,
-      const webrtc::SdpVideoFormat& format) override;
+  std::vector<SdpVideoFormat> GetSupportedFormats() const override;
+  std::unique_ptr<VideoDecoder> Create(const Environment& env,
+                                       const SdpVideoFormat& format) override;
 
   void DecoderDestroyed(FakeWebRtcVideoDecoder* decoder);
-  void AddSupportedVideoCodec(const webrtc::SdpVideoFormat& format);
+  void AddSupportedVideoCodec(const SdpVideoFormat& format);
   void AddSupportedVideoCodecType(const std::string& name);
   int GetNumCreatedDecoders();
   const std::vector<FakeWebRtcVideoDecoder*>& decoders();
 
  private:
-  std::vector<webrtc::SdpVideoFormat> supported_codec_formats_;
+  std::vector<SdpVideoFormat> supported_codec_formats_;
   std::vector<FakeWebRtcVideoDecoder*> decoders_;
   int num_created_decoders_;
 };
 
 // Fake class for mocking out webrtc::VideoEnoder
-class FakeWebRtcVideoEncoder : public webrtc::VideoEncoder {
+class FakeWebRtcVideoEncoder : public VideoEncoder {
  public:
   explicit FakeWebRtcVideoEncoder(FakeWebRtcVideoEncoderFactory* factory);
   ~FakeWebRtcVideoEncoder();
 
   void SetFecControllerOverride(
-      webrtc::FecControllerOverride* fec_controller_override) override;
-  int32_t InitEncode(const webrtc::VideoCodec* codecSettings,
+      FecControllerOverride* fec_controller_override) override;
+  int32_t InitEncode(const VideoCodec* codecSettings,
                      const VideoEncoder::Settings& settings) override;
-  int32_t Encode(
-      const webrtc::VideoFrame& inputImage,
-      const std::vector<webrtc::VideoFrameType>* frame_types) override;
+  int32_t Encode(const VideoFrame& inputImage,
+                 const std::vector<VideoFrameType>* frame_types) override;
   int32_t RegisterEncodeCompleteCallback(
-      webrtc::EncodedImageCallback* callback) override;
+      EncodedImageCallback* callback) override;
   int32_t Release() override;
   void SetRates(const RateControlParameters& parameters) override;
-  webrtc::VideoEncoder::EncoderInfo GetEncoderInfo() const override;
+  VideoEncoder::EncoderInfo GetEncoderInfo() const override;
 
   bool WaitForInitEncode();
-  webrtc::VideoCodec GetCodecSettings();
+  VideoCodec GetCodecSettings();
   int GetNumEncodedFrames();
 
  private:
-  webrtc::Mutex mutex_;
+  Mutex mutex_;
   rtc::Event init_encode_event_;
   int num_frames_encoded_ RTC_GUARDED_BY(mutex_);
-  webrtc::VideoCodec codec_settings_ RTC_GUARDED_BY(mutex_);
+  VideoCodec codec_settings_ RTC_GUARDED_BY(mutex_);
   FakeWebRtcVideoEncoderFactory* factory_;
 };
 
 // Fake class for mocking out webrtc::VideoEncoderFactory.
-class FakeWebRtcVideoEncoderFactory : public webrtc::VideoEncoderFactory {
+class FakeWebRtcVideoEncoderFactory : public VideoEncoderFactory {
  public:
   FakeWebRtcVideoEncoderFactory();
 
-  std::vector<webrtc::SdpVideoFormat> GetSupportedFormats() const override;
-  webrtc::VideoEncoderFactory::CodecSupport QueryCodecSupport(
-      const webrtc::SdpVideoFormat& format,
+  std::vector<SdpVideoFormat> GetSupportedFormats() const override;
+  VideoEncoderFactory::CodecSupport QueryCodecSupport(
+      const SdpVideoFormat& format,
       std::optional<std::string> scalability_mode) const override;
-  std::unique_ptr<webrtc::VideoEncoder> Create(
-      const webrtc::Environment& env,
-      const webrtc::SdpVideoFormat& format) override;
+  std::unique_ptr<VideoEncoder> Create(const Environment& env,
+                                       const SdpVideoFormat& format) override;
 
   bool WaitForCreatedVideoEncoders(int num_encoders);
   void EncoderDestroyed(FakeWebRtcVideoEncoder* encoder);
   void set_encoders_have_internal_sources(bool internal_source);
-  void AddSupportedVideoCodec(const webrtc::SdpVideoFormat& format);
+  void AddSupportedVideoCodec(const SdpVideoFormat& format);
   void AddSupportedVideoCodecType(
       const std::string& name,
-      const std::vector<webrtc::ScalabilityMode>& scalability_modes = {});
+      const std::vector<ScalabilityMode>& scalability_modes = {});
   int GetNumCreatedEncoders();
   const std::vector<FakeWebRtcVideoEncoder*> encoders();
 
  private:
-  webrtc::Mutex mutex_;
+  Mutex mutex_;
   rtc::Event created_video_encoder_event_;
-  std::vector<webrtc::SdpVideoFormat> formats_;
+  std::vector<SdpVideoFormat> formats_;
   std::vector<FakeWebRtcVideoEncoder*> encoders_ RTC_GUARDED_BY(mutex_);
   int num_created_encoders_ RTC_GUARDED_BY(mutex_);
   bool vp8_factory_mode_;
 };
 
+}  //  namespace webrtc
+
+// Re-export symbols from the webrtc namespace for backwards compatibility.
+// TODO(bugs.webrtc.org/4222596): Remove once all references are updated.
+namespace cricket {
+using ::webrtc::FakeWebRtcVideoDecoder;
+using ::webrtc::FakeWebRtcVideoDecoderFactory;
+using ::webrtc::FakeWebRtcVideoEncoder;
+using ::webrtc::FakeWebRtcVideoEncoderFactory;
 }  // namespace cricket
 
 #endif  // MEDIA_ENGINE_FAKE_WEBRTC_VIDEO_ENGINE_H_
diff --git a/media/engine/webrtc_video_engine_unittest.cc b/media/engine/webrtc_video_engine_unittest.cc
index 23e85ab..39d9bfc 100644
--- a/media/engine/webrtc_video_engine_unittest.cc
+++ b/media/engine/webrtc_video_engine_unittest.cc
@@ -406,13 +406,13 @@
                                time_controller_.CreateTaskQueueFactory(),
                                time_controller_.GetClock())),
         call_(Call::Create(CallConfig(env_))),
-        encoder_factory_(new cricket::FakeWebRtcVideoEncoderFactory),
-        decoder_factory_(new cricket::FakeWebRtcVideoDecoderFactory),
+        encoder_factory_(new webrtc::FakeWebRtcVideoEncoderFactory),
+        decoder_factory_(new webrtc::FakeWebRtcVideoDecoderFactory),
         video_bitrate_allocator_factory_(
             webrtc::CreateBuiltinVideoBitrateAllocatorFactory()),
-        engine_(std::unique_ptr<cricket::FakeWebRtcVideoEncoderFactory>(
+        engine_(std::unique_ptr<webrtc::FakeWebRtcVideoEncoderFactory>(
                     encoder_factory_),
-                std::unique_ptr<cricket::FakeWebRtcVideoDecoderFactory>(
+                std::unique_ptr<webrtc::FakeWebRtcVideoDecoderFactory>(
                     decoder_factory_),
                 field_trials_) {}
 
@@ -448,8 +448,8 @@
   // Used in WebRtcVideoEngineVoiceTest, but defined here so it's properly
   // initialized when the constructor is called.
   std::unique_ptr<Call> call_;
-  cricket::FakeWebRtcVideoEncoderFactory* encoder_factory_;
-  cricket::FakeWebRtcVideoDecoderFactory* decoder_factory_;
+  webrtc::FakeWebRtcVideoEncoderFactory* encoder_factory_;
+  webrtc::FakeWebRtcVideoDecoderFactory* decoder_factory_;
   std::unique_ptr<webrtc::VideoBitrateAllocatorFactory>
       video_bitrate_allocator_factory_;
   WebRtcVideoEngine engine_;
@@ -772,8 +772,8 @@
   EXPECT_EQ(0, encoder_factory_->GetNumCreatedEncoders());
   EXPECT_TRUE(send_channel->SetSend(true));
   webrtc::test::FrameForwarder frame_forwarder;
-  cricket::FakeFrameSource frame_source(1280, 720,
-                                        rtc::kNumMicrosecsPerSec / 30);
+  webrtc::FakeFrameSource frame_source(1280, 720,
+                                       rtc::kNumMicrosecsPerSec / 30);
   EXPECT_TRUE(send_channel->SetVideoSend(kSsrc, nullptr, &frame_forwarder));
   frame_forwarder.IncomingCapturedFrame(frame_source.GetFrame());
   time_controller_.AdvanceTime(webrtc::TimeDelta::Zero());
@@ -852,7 +852,7 @@
 
 TEST_F(WebRtcVideoEngineTest, PropagatesInputFrameTimestamp) {
   AddSupportedVideoCodecType("VP8");
-  FakeCall* fake_call = new FakeCall(env_);
+  webrtc::FakeCall* fake_call = new webrtc::FakeCall(env_);
   call_.reset(fake_call);
   auto send_channel = SetSendParamsWithAllSupportedCodecs();
 
@@ -860,12 +860,12 @@
       send_channel->AddSendStream(cricket::StreamParams::CreateLegacy(kSsrc)));
 
   webrtc::test::FrameForwarder frame_forwarder;
-  cricket::FakeFrameSource frame_source(1280, 720,
-                                        rtc::kNumMicrosecsPerSec / 60);
+  webrtc::FakeFrameSource frame_source(1280, 720,
+                                       rtc::kNumMicrosecsPerSec / 60);
   EXPECT_TRUE(send_channel->SetVideoSend(kSsrc, nullptr, &frame_forwarder));
   send_channel->SetSend(true);
 
-  FakeVideoSendStream* stream = fake_call->GetVideoSendStreams()[0];
+  webrtc::FakeVideoSendStream* stream = fake_call->GetVideoSendStreams()[0];
 
   frame_forwarder.IncomingCapturedFrame(frame_source.GetFrame());
   int64_t last_timestamp = stream->GetLastTimestamp();
@@ -1039,7 +1039,7 @@
   std::unique_ptr<VideoMediaReceiveChannelInterface> receive_channel =
       engine_.CreateReceiveChannel(call_.get(), GetMediaConfig(),
                                    VideoOptions(), webrtc::CryptoOptions());
-  cricket::FakeNetworkInterface network;
+  webrtc::FakeNetworkInterface network;
   receive_channel->SetInterface(&network);
   EXPECT_EQ(10000, network.recvbuf_size());
   receive_channel->SetInterface(nullptr);
@@ -1053,7 +1053,7 @@
   std::unique_ptr<VideoMediaReceiveChannelInterface> receive_channel =
       engine_.CreateReceiveChannel(call_.get(), GetMediaConfig(),
                                    VideoOptions(), webrtc::CryptoOptions());
-  cricket::FakeNetworkInterface network;
+  webrtc::FakeNetworkInterface network;
   receive_channel->SetInterface(&network);
   EXPECT_EQ(kVideoRtpRecvBufferSize, network.recvbuf_size());
   receive_channel->SetInterface(nullptr);
@@ -1066,7 +1066,7 @@
   std::unique_ptr<VideoMediaReceiveChannelInterface> receive_channel =
       engine_.CreateReceiveChannel(call_.get(), GetMediaConfig(),
                                    VideoOptions(), webrtc::CryptoOptions());
-  cricket::FakeNetworkInterface network;
+  webrtc::FakeNetworkInterface network;
   receive_channel->SetInterface(&network);
   EXPECT_EQ(kVideoRtpRecvBufferSize, network.recvbuf_size());
   receive_channel->SetInterface(nullptr);
@@ -1123,13 +1123,13 @@
 
   std::vector<uint32_t> ssrcs = MAKE_VECTOR(kSsrcs3);
 
-  EXPECT_TRUE(
-      send_channel->AddSendStream(CreateSimStreamParams("cname", ssrcs)));
+  EXPECT_TRUE(send_channel->AddSendStream(
+      webrtc::CreateSimStreamParams("cname", ssrcs)));
   EXPECT_TRUE(send_channel->SetSend(true));
 
   webrtc::test::FrameForwarder frame_forwarder;
-  cricket::FakeFrameSource frame_source(1280, 720,
-                                        rtc::kNumMicrosecsPerSec / 60);
+  webrtc::FakeFrameSource frame_source(1280, 720,
+                                       rtc::kNumMicrosecsPerSec / 60);
   EXPECT_TRUE(
       send_channel->SetVideoSend(ssrcs.front(), nullptr, &frame_forwarder));
   frame_forwarder.IncomingCapturedFrame(frame_source.GetFrame());
@@ -1160,8 +1160,8 @@
 
   // Frame source.
   webrtc::test::FrameForwarder frame_forwarder;
-  cricket::FakeFrameSource frame_source(1280, 720,
-                                        rtc::kNumMicrosecsPerSec / 30);
+  webrtc::FakeFrameSource frame_source(1280, 720,
+                                       rtc::kNumMicrosecsPerSec / 30);
 
   std::unique_ptr<VideoMediaSendChannelInterface> send_channel =
       engine_.CreateSendChannel(call_.get(), GetMediaConfig(), VideoOptions(),
@@ -1206,16 +1206,16 @@
 
   std::vector<uint32_t> ssrcs = MAKE_VECTOR(kSsrcs3);
 
-  EXPECT_TRUE(
-      send_channel->AddSendStream(CreateSimStreamParams("cname", ssrcs)));
+  EXPECT_TRUE(send_channel->AddSendStream(
+      webrtc::CreateSimStreamParams("cname", ssrcs)));
   EXPECT_TRUE(send_channel->SetSend(true));
 
   // Send a fake frame, or else the media engine will configure the simulcast
   // encoder adapter at a low-enough size that it'll only create a single
   // encoder layer.
   webrtc::test::FrameForwarder frame_forwarder;
-  cricket::FakeFrameSource frame_source(1280, 720,
-                                        rtc::kNumMicrosecsPerSec / 30);
+  webrtc::FakeFrameSource frame_source(1280, 720,
+                                       rtc::kNumMicrosecsPerSec / 30);
   EXPECT_TRUE(
       send_channel->SetVideoSend(ssrcs.front(), nullptr, &frame_forwarder));
   frame_forwarder.IncomingCapturedFrame(frame_source.GetFrame());
@@ -1249,8 +1249,8 @@
 
   // Send a frame of 720p. This should trigger a "real" encoder initialization.
   webrtc::test::FrameForwarder frame_forwarder;
-  cricket::FakeFrameSource frame_source(1280, 720,
-                                        rtc::kNumMicrosecsPerSec / 30);
+  webrtc::FakeFrameSource frame_source(1280, 720,
+                                       rtc::kNumMicrosecsPerSec / 30);
   EXPECT_TRUE(send_channel->SetVideoSend(kSsrc, nullptr, &frame_forwarder));
   frame_forwarder.IncomingCapturedFrame(frame_source.GetFrame());
   time_controller_.AdvanceTime(webrtc::TimeDelta::Zero());
@@ -1279,19 +1279,19 @@
 
   const std::vector<uint32_t> ssrcs = MAKE_VECTOR(kSsrcs3);
   EXPECT_TRUE(send_channel->AddSendStream(
-      cricket::CreateSimStreamParams("cname", ssrcs)));
+      webrtc::CreateSimStreamParams("cname", ssrcs)));
 
   // Send a frame of 720p. This should trigger a "real" encoder initialization.
   webrtc::test::FrameForwarder frame_forwarder;
-  cricket::FakeFrameSource frame_source(1280, 720,
-                                        rtc::kNumMicrosecsPerSec / 30);
+  webrtc::FakeFrameSource frame_source(1280, 720,
+                                       rtc::kNumMicrosecsPerSec / 30);
   EXPECT_TRUE(send_channel->SetVideoSend(ssrcs[0], nullptr, &frame_forwarder));
   frame_forwarder.IncomingCapturedFrame(frame_source.GetFrame());
   time_controller_.AdvanceTime(webrtc::TimeDelta::Zero());
 
   ASSERT_TRUE(encoder_factory_->WaitForCreatedVideoEncoders(1));
   ASSERT_EQ(1u, encoder_factory_->encoders().size());
-  FakeWebRtcVideoEncoder* encoder = encoder_factory_->encoders()[0];
+  webrtc::FakeWebRtcVideoEncoder* encoder = encoder_factory_->encoders()[0];
   ASSERT_TRUE(encoder_factory_->encoders()[0]->WaitForInitEncode());
   EXPECT_EQ(webrtc::kVideoCodecH264, encoder->GetCodecSettings().codecType);
   EXPECT_LT(1u, encoder->GetCodecSettings().numberOfSimulcastStreams);
@@ -1526,7 +1526,7 @@
   // Mock encoder creation. `engine` take ownership of the encoder.
   const webrtc::SdpVideoFormat format("VP8");
   EXPECT_CALL(*encoder_factory, Create(_, format)).WillOnce([&] {
-    return std::make_unique<FakeWebRtcVideoEncoder>(nullptr);
+    return std::make_unique<webrtc::FakeWebRtcVideoEncoder>(nullptr);
   });
 
   // Expect no decoder to be created at this point. The decoder will only be
@@ -1557,8 +1557,8 @@
 
   // Set capturer.
   webrtc::test::FrameForwarder frame_forwarder;
-  cricket::FakeFrameSource frame_source(1280, 720,
-                                        rtc::kNumMicrosecsPerSec / 30);
+  webrtc::FakeFrameSource frame_source(1280, 720,
+                                       rtc::kNumMicrosecsPerSec / 30);
   EXPECT_TRUE(send_channel->SetVideoSend(send_ssrc, nullptr, &frame_forwarder));
   // Sending one frame will allocate the encoder.
   frame_forwarder.IncomingCapturedFrame(frame_source.GetFrame());
@@ -1586,7 +1586,7 @@
 
 TEST_F(WebRtcVideoEngineTest, DISABLED_RecreatesEncoderOnContentTypeChange) {
   encoder_factory_->AddSupportedVideoCodecType("VP8");
-  auto fake_call = std::make_unique<FakeCall>(env_);
+  auto fake_call = std::make_unique<webrtc::FakeCall>(env_);
   auto send_channel = SetSendParamsWithAllSupportedCodecs();
 
   ASSERT_TRUE(
@@ -1599,8 +1599,8 @@
   ASSERT_TRUE(send_channel->SetSenderParameters(parameters));
 
   webrtc::test::FrameForwarder frame_forwarder;
-  cricket::FakeFrameSource frame_source(1280, 720,
-                                        rtc::kNumMicrosecsPerSec / 30);
+  webrtc::FakeFrameSource frame_source(1280, 720,
+                                       rtc::kNumMicrosecsPerSec / 30);
   VideoOptions options;
   EXPECT_TRUE(send_channel->SetVideoSend(kSsrc, &options, &frame_forwarder));
 
@@ -1727,8 +1727,8 @@
   WebRtcVideoEngine engine_;
   std::unique_ptr<VideoMediaSendChannelInterface> send_channel_;
   std::unique_ptr<VideoMediaReceiveChannelInterface> receive_channel_;
-  cricket::FakeNetworkInterface network_interface_;
-  cricket::FakeVideoRenderer renderer_;
+  webrtc::FakeNetworkInterface network_interface_;
+  webrtc::FakeVideoRenderer renderer_;
 };
 
 const std::vector<webrtc::SdpVideoFormat>
@@ -1884,7 +1884,7 @@
     receive_channel_->SetReceiverParameters(parameters);
     EXPECT_TRUE(send_channel_->AddSendStream(DefaultSendStreamParams()));
     frame_forwarder_ = std::make_unique<webrtc::test::FrameForwarder>();
-    frame_source_ = std::make_unique<cricket::FakeFrameSource>(
+    frame_source_ = std::make_unique<webrtc::FakeFrameSource>(
         640, 480, rtc::kNumMicrosecsPerSec / kFramerate);
     EXPECT_TRUE(
         send_channel_->SetVideoSend(kSsrc, nullptr, frame_forwarder_.get()));
@@ -1942,7 +1942,7 @@
   bool SetDefaultCodec() { return SetOneCodec(DefaultCodec()); }
 
   bool SetOneCodec(const cricket::Codec& codec) {
-    frame_source_ = std::make_unique<cricket::FakeFrameSource>(
+    frame_source_ = std::make_unique<webrtc::FakeFrameSource>(
         kVideoWidth, kVideoHeight, rtc::kNumMicrosecsPerSec / kFramerate);
 
     bool sending = SendImpl()->sending();
@@ -2066,17 +2066,17 @@
       video_bitrate_allocator_factory_;
   WebRtcVideoEngine engine_;
 
-  std::unique_ptr<cricket::FakeFrameSource> frame_source_;
+  std::unique_ptr<webrtc::FakeFrameSource> frame_source_;
   std::unique_ptr<webrtc::test::FrameForwarder> frame_forwarder_;
   std::unique_ptr<webrtc::test::FrameForwarder> frame_forwarder_2_;
 
   std::unique_ptr<VideoMediaSendChannelInterface> send_channel_;
   std::unique_ptr<VideoMediaReceiveChannelInterface> receive_channel_;
-  cricket::FakeNetworkInterface network_interface_;
-  cricket::FakeVideoRenderer renderer_;
+  webrtc::FakeNetworkInterface network_interface_;
+  webrtc::FakeVideoRenderer renderer_;
 
   // Used by test cases where 2 streams are run on the same channel.
-  cricket::FakeVideoRenderer renderer2_;
+  webrtc::FakeVideoRenderer renderer2_;
 };
 
 // Test that SetSend works.
@@ -2173,7 +2173,7 @@
 
 // Test that stats work properly for a conf call with multiple recv streams.
 TEST_F(WebRtcVideoChannelBaseTest, GetStatsMultipleRecvStreams) {
-  cricket::FakeVideoRenderer renderer1, renderer2;
+  webrtc::FakeVideoRenderer renderer1, renderer2;
   EXPECT_TRUE(SetOneCodec(DefaultCodec()));
   cricket::VideoSenderParameters parameters;
   parameters.codecs.push_back(DefaultCodec());
@@ -2242,12 +2242,12 @@
   EXPECT_FRAME(1, kVideoWidth, kVideoHeight);
 
   // Add an additional capturer, and hook up a renderer to receive it.
-  cricket::FakeVideoRenderer renderer2;
+  webrtc::FakeVideoRenderer renderer2;
   webrtc::test::FrameForwarder frame_forwarder;
   const int kTestWidth = 160;
   const int kTestHeight = 120;
-  cricket::FakeFrameSource frame_source(kTestWidth, kTestHeight,
-                                        rtc::kNumMicrosecsPerSec / 5);
+  webrtc::FakeFrameSource frame_source(kTestWidth, kTestHeight,
+                                       rtc::kNumMicrosecsPerSec / 5);
   EXPECT_TRUE(
       send_channel_->AddSendStream(cricket::StreamParams::CreateLegacy(5678)));
   EXPECT_TRUE(send_channel_->SetVideoSend(5678, nullptr, &frame_forwarder));
@@ -2379,7 +2379,7 @@
 
 // Tests the behavior of incoming streams in a conference scenario.
 TEST_F(WebRtcVideoChannelBaseTest, SimulateConference) {
-  cricket::FakeVideoRenderer renderer1, renderer2;
+  webrtc::FakeVideoRenderer renderer1, renderer2;
   EXPECT_TRUE(SetDefaultCodec());
   cricket::VideoSenderParameters parameters;
   parameters.codecs.push_back(DefaultCodec());
@@ -2428,8 +2428,8 @@
   EXPECT_FRAME(1, kVideoWidth, kVideoHeight);
 
   webrtc::test::FrameForwarder frame_forwarder;
-  cricket::FakeFrameSource frame_source(480, 360, rtc::kNumMicrosecsPerSec / 30,
-                                        rtc::kNumMicrosecsPerSec / 30);
+  webrtc::FakeFrameSource frame_source(480, 360, rtc::kNumMicrosecsPerSec / 30,
+                                       rtc::kNumMicrosecsPerSec / 30);
 
   // TODO(nisse): This testcase fails if we don't configure
   // screencast. It's unclear why, I see nothing obvious in this
@@ -2507,7 +2507,7 @@
       kVideoWidth, kVideoHeight,
       cricket::VideoFormat::FpsToInterval(kFramerate), cricket::FOURCC_I420);
   // Set up additional stream 1.
-  cricket::FakeVideoRenderer renderer1;
+  webrtc::FakeVideoRenderer renderer1;
   EXPECT_FALSE(receive_channel_->SetSink(1, &renderer1));
   EXPECT_TRUE(
       receive_channel_->AddRecvStream(cricket::StreamParams::CreateLegacy(1)));
@@ -2516,11 +2516,11 @@
       send_channel_->AddSendStream(cricket::StreamParams::CreateLegacy(1)));
 
   webrtc::test::FrameForwarder frame_forwarder1;
-  cricket::FakeFrameSource frame_source(kVideoWidth, kVideoHeight,
-                                        rtc::kNumMicrosecsPerSec / kFramerate);
+  webrtc::FakeFrameSource frame_source(kVideoWidth, kVideoHeight,
+                                       rtc::kNumMicrosecsPerSec / kFramerate);
 
   // Set up additional stream 2.
-  cricket::FakeVideoRenderer renderer2;
+  webrtc::FakeVideoRenderer renderer2;
   EXPECT_FALSE(receive_channel_->SetSink(2, &renderer2));
   EXPECT_TRUE(
       receive_channel_->AddRecvStream(cricket::StreamParams::CreateLegacy(2)));
@@ -2764,7 +2764,7 @@
     AddSupportedVideoCodecType("H264");
 #endif
 
-    fake_call_ = std::make_unique<FakeCall>(env_);
+    fake_call_ = std::make_unique<webrtc::FakeCall>(env_);
     send_channel_ = engine_.CreateSendChannel(
         fake_call_.get(), GetMediaConfig(), VideoOptions(),
         webrtc::CryptoOptions(), video_bitrate_allocator_factory_.get());
@@ -2837,31 +2837,31 @@
   }
 
  protected:
-  FakeVideoSendStream* AddSendStream() {
+  webrtc::FakeVideoSendStream* AddSendStream() {
     return AddSendStream(StreamParams::CreateLegacy(++last_ssrc_));
   }
 
-  FakeVideoSendStream* AddSendStream(const StreamParams& sp) {
+  webrtc::FakeVideoSendStream* AddSendStream(const StreamParams& sp) {
     size_t num_streams = fake_call_->GetVideoSendStreams().size();
     EXPECT_TRUE(send_channel_->AddSendStream(sp));
-    std::vector<FakeVideoSendStream*> streams =
+    std::vector<webrtc::FakeVideoSendStream*> streams =
         fake_call_->GetVideoSendStreams();
     EXPECT_EQ(num_streams + 1, streams.size());
     return streams[streams.size() - 1];
   }
 
-  std::vector<FakeVideoSendStream*> GetFakeSendStreams() {
+  std::vector<webrtc::FakeVideoSendStream*> GetFakeSendStreams() {
     return fake_call_->GetVideoSendStreams();
   }
 
-  FakeVideoReceiveStream* AddRecvStream() {
+  webrtc::FakeVideoReceiveStream* AddRecvStream() {
     return AddRecvStream(StreamParams::CreateLegacy(++last_ssrc_));
   }
 
-  FakeVideoReceiveStream* AddRecvStream(const StreamParams& sp) {
+  webrtc::FakeVideoReceiveStream* AddRecvStream(const StreamParams& sp) {
     size_t num_streams = fake_call_->GetVideoReceiveStreams().size();
     EXPECT_TRUE(receive_channel_->AddRecvStream(sp));
-    std::vector<FakeVideoReceiveStream*> streams =
+    std::vector<webrtc::FakeVideoReceiveStream*> streams =
         fake_call_->GetVideoReceiveStreams();
     EXPECT_EQ(num_streams + 1, streams.size());
     return streams[streams.size() - 1];
@@ -2931,7 +2931,7 @@
     cricket::VideoSenderParameters parameters = send_parameters_;
     parameters.extensions.push_back(RtpExtension(ext_uri, id));
     EXPECT_TRUE(send_channel_->SetSenderParameters(parameters));
-    FakeVideoSendStream* send_stream =
+    webrtc::FakeVideoSendStream* send_stream =
         AddSendStream(cricket::StreamParams::CreateLegacy(123));
 
     // Verify the send extension id.
@@ -3000,12 +3000,12 @@
     EXPECT_TRUE(send_channel_->SetSend(true));
 
     // Send side.
-    FakeVideoSendStream* send_stream =
+    webrtc::FakeVideoSendStream* send_stream =
         AddSendStream(cricket::StreamParams::CreateLegacy(1));
     EXPECT_EQ(send_stream->GetConfig().rtp.lntf.enabled, expect_lntf_enabled);
 
     // Receiver side.
-    FakeVideoReceiveStream* recv_stream =
+    webrtc::FakeVideoReceiveStream* recv_stream =
         AddRecvStream(cricket::StreamParams::CreateLegacy(1));
     EXPECT_EQ(recv_stream->GetConfig().rtp.lntf.enabled, expect_lntf_enabled);
   }
@@ -3021,7 +3021,7 @@
       parameters.extensions.push_back(RtpExtension(extension, id++));
     }
     EXPECT_TRUE(send_channel_->SetSenderParameters(parameters));
-    FakeVideoSendStream* send_stream =
+    webrtc::FakeVideoSendStream* send_stream =
         AddSendStream(cricket::StreamParams::CreateLegacy(123));
 
     // Verify that only one of them has been set, and that it is the one with
@@ -3040,7 +3040,7 @@
   void TestReceiveUnsignaledSsrcPacket(uint8_t payload_type,
                                        bool expect_created_receive_stream);
 
-  FakeVideoSendStream* SetDenoisingOption(
+  webrtc::FakeVideoSendStream* SetDenoisingOption(
       uint32_t ssrc,
       webrtc::test::FrameForwarder* frame_forwarder,
       bool enabled) {
@@ -3053,7 +3053,7 @@
     return fake_call_->GetVideoSendStreams().back();
   }
 
-  FakeVideoSendStream* SetUpSimulcast(bool enabled, bool with_rtx) {
+  webrtc::FakeVideoSendStream* SetUpSimulcast(bool enabled, bool with_rtx) {
     const int kRtxSsrcOffset = 0xDEADBEEF;
     last_ssrc_ += 3;
     std::vector<uint32_t> ssrcs;
@@ -3068,16 +3068,16 @@
     }
     if (with_rtx) {
       return AddSendStream(
-          cricket::CreateSimWithRtxStreamParams("cname", ssrcs, rtx_ssrcs));
+          webrtc::CreateSimWithRtxStreamParams("cname", ssrcs, rtx_ssrcs));
     }
-    return AddSendStream(CreateSimStreamParams("cname", ssrcs));
+    return AddSendStream(webrtc::CreateSimStreamParams("cname", ssrcs));
   }
 
   int GetMaxEncoderBitrate() {
-    std::vector<FakeVideoSendStream*> streams =
+    std::vector<webrtc::FakeVideoSendStream*> streams =
         fake_call_->GetVideoSendStreams();
     EXPECT_EQ(1u, streams.size());
-    FakeVideoSendStream* stream = streams[streams.size() - 1];
+    webrtc::FakeVideoSendStream* stream = streams[streams.size() - 1];
     EXPECT_EQ(1u, stream->GetEncoderConfig().number_of_streams);
     return stream->GetVideoStreams()[0].max_bitrate_bps;
   }
@@ -3117,8 +3117,8 @@
     return layers;
   }
 
-  cricket::FakeFrameSource frame_source_;
-  std::unique_ptr<FakeCall> fake_call_;
+  webrtc::FakeFrameSource frame_source_;
+  std::unique_ptr<webrtc::FakeCall> fake_call_;
   std::unique_ptr<VideoMediaSendChannelInterface> send_channel_;
   std::unique_ptr<VideoMediaReceiveChannelInterface> receive_channel_;
   cricket::VideoSenderParameters send_parameters_;
@@ -3151,16 +3151,16 @@
   // Send side.
   const std::vector<uint32_t> ssrcs = MAKE_VECTOR(kSsrcs1);
   const std::vector<uint32_t> rtx_ssrcs = MAKE_VECTOR(kRtxSsrcs1);
-  FakeVideoSendStream* send_stream = AddSendStream(
-      cricket::CreateSimWithRtxStreamParams("cname", ssrcs, rtx_ssrcs));
+  webrtc::FakeVideoSendStream* send_stream = AddSendStream(
+      webrtc::CreateSimWithRtxStreamParams("cname", ssrcs, rtx_ssrcs));
 
   ASSERT_EQ(rtx_ssrcs.size(), send_stream->GetConfig().rtp.rtx.ssrcs.size());
   for (size_t i = 0; i < rtx_ssrcs.size(); ++i)
     EXPECT_EQ(rtx_ssrcs[i], send_stream->GetConfig().rtp.rtx.ssrcs[i]);
 
   // Receiver side.
-  FakeVideoReceiveStream* recv_stream = AddRecvStream(
-      cricket::CreateSimWithRtxStreamParams("cname", ssrcs, rtx_ssrcs));
+  webrtc::FakeVideoReceiveStream* recv_stream = AddRecvStream(
+      webrtc::CreateSimWithRtxStreamParams("cname", ssrcs, rtx_ssrcs));
   EXPECT_FALSE(
       recv_stream->GetConfig().rtp.rtx_associated_payload_types.empty());
   EXPECT_TRUE(VerifyRtxReceiveAssociations(recv_stream->GetConfig()))
@@ -3177,7 +3177,7 @@
   cricket::StreamParams params =
       cricket::StreamParams::CreateLegacy(kSsrcs1[0]);
   params.AddFidSsrc(kSsrcs1[0], kRtxSsrcs1[0]);
-  FakeVideoReceiveStream* recv_stream = AddRecvStream(params);
+  webrtc::FakeVideoReceiveStream* recv_stream = AddRecvStream(params);
   EXPECT_EQ(kRtxSsrcs1[0], recv_stream->GetConfig().rtp.rtx_ssrc);
 
   EXPECT_TRUE(VerifyRtxReceiveAssociations(recv_stream->GetConfig()))
@@ -3191,7 +3191,7 @@
   // Setup one channel without an associated RTX stream.
   cricket::StreamParams params =
       cricket::StreamParams::CreateLegacy(kSsrcs1[0]);
-  FakeVideoReceiveStream* recv_stream = AddRecvStream(params);
+  webrtc::FakeVideoReceiveStream* recv_stream = AddRecvStream(params);
   ASSERT_EQ(0U, recv_stream->GetConfig().rtp.rtx_ssrc);
 }
 
@@ -3210,7 +3210,7 @@
 }
 
 TEST_F(WebRtcVideoChannelTest, NoHeaderExtesionsByDefault) {
-  FakeVideoSendStream* send_stream =
+  webrtc::FakeVideoSendStream* send_stream =
       AddSendStream(cricket::StreamParams::CreateLegacy(kSsrcs1[0]));
   ASSERT_TRUE(send_stream->GetConfig().rtp.extensions.empty());
 
@@ -3281,7 +3281,7 @@
 
 TEST_F(WebRtcVideoChannelTest, DisableFrameInstrumentationByDefault) {
   EXPECT_TRUE(send_channel_->SetSenderParameters(send_parameters_));
-  FakeVideoSendStream* send_stream =
+  webrtc::FakeVideoSendStream* send_stream =
       AddSendStream(cricket::StreamParams::CreateLegacy(123));
   EXPECT_FALSE(send_stream->GetConfig()
                    .encoder_settings.enable_frame_instrumentation_generator);
@@ -3294,7 +3294,7 @@
       RtpExtension::kCorruptionDetectionUri, /*id=*/1, /*encrypt=*/true));
   EXPECT_TRUE(send_channel_->SetSenderParameters(parameters));
 
-  FakeVideoSendStream* send_stream =
+  webrtc::FakeVideoSendStream* send_stream =
       AddSendStream(cricket::StreamParams::CreateLegacy(123));
   EXPECT_TRUE(send_stream->GetConfig()
                   .encoder_settings.enable_frame_instrumentation_generator);
@@ -3307,7 +3307,7 @@
       RtpExtension::kCorruptionDetectionUri, /*id=*/1, /*encrypt=*/false));
   EXPECT_TRUE(send_channel_->SetSenderParameters(parameters));
 
-  FakeVideoSendStream* send_stream =
+  webrtc::FakeVideoSendStream* send_stream =
       AddSendStream(cricket::StreamParams::CreateLegacy(123));
   EXPECT_FALSE(send_stream->GetConfig()
                    .encoder_settings.enable_frame_instrumentation_generator);
@@ -3322,7 +3322,7 @@
       RtpExtension(RtpExtension::kVideoRotationUri, kVideoRotationId));
 
   EXPECT_TRUE(send_channel_->SetSenderParameters(send_parameters_));
-  FakeVideoSendStream* send_stream =
+  webrtc::FakeVideoSendStream* send_stream =
       AddSendStream(cricket::StreamParams::CreateLegacy(123));
 
   EXPECT_EQ(1, fake_call_->GetNumCreatedSendStreams());
@@ -3352,7 +3352,7 @@
   send_parameters_.extensions.push_back(
       RtpExtension(RtpExtension::kTimestampOffsetUri, kTOffsetId));
   EXPECT_TRUE(send_channel_->SetSenderParameters(send_parameters_));
-  FakeVideoSendStream* send_stream =
+  webrtc::FakeVideoSendStream* send_stream =
       AddSendStream(cricket::StreamParams::CreateLegacy(123));
 
   // Only timestamp offset extension is set to send stream,
@@ -3464,7 +3464,7 @@
 }
 
 TEST_F(WebRtcVideoChannelTest, RtcpIsCompoundByDefault) {
-  FakeVideoReceiveStream* stream = AddRecvStream();
+  webrtc::FakeVideoReceiveStream* stream = AddRecvStream();
   EXPECT_EQ(webrtc::RtcpMode::kCompound, stream->GetConfig().rtp.rtcp_mode);
 }
 
@@ -3495,10 +3495,10 @@
   }
 
   // Start with LNTF enabled.
-  FakeVideoSendStream* send_stream =
+  webrtc::FakeVideoSendStream* send_stream =
       AddSendStream(cricket::StreamParams::CreateLegacy(1));
   ASSERT_TRUE(send_stream->GetConfig().rtp.lntf.enabled);
-  FakeVideoReceiveStream* recv_stream =
+  webrtc::FakeVideoReceiveStream* recv_stream =
       AddRecvStream(cricket::StreamParams::CreateLegacy(1));
   ASSERT_TRUE(recv_stream->GetConfig().rtp.lntf.enabled);
 
@@ -3531,12 +3531,12 @@
   EXPECT_TRUE(send_channel_->SetSend(true));
 
   // Send side.
-  FakeVideoSendStream* send_stream =
+  webrtc::FakeVideoSendStream* send_stream =
       AddSendStream(cricket::StreamParams::CreateLegacy(1));
   EXPECT_GT(send_stream->GetConfig().rtp.nack.rtp_history_ms, 0);
 
   // Receiver side.
-  FakeVideoReceiveStream* recv_stream =
+  webrtc::FakeVideoReceiveStream* recv_stream =
       AddRecvStream(cricket::StreamParams::CreateLegacy(1));
   EXPECT_GT(recv_stream->GetConfig().rtp.nack.rtp_history_ms, 0);
 
@@ -3546,8 +3546,8 @@
 }
 
 TEST_F(WebRtcVideoChannelTest, NackCanBeEnabledAndDisabled) {
-  FakeVideoSendStream* send_stream = AddSendStream();
-  FakeVideoReceiveStream* recv_stream = AddRecvStream();
+  webrtc::FakeVideoSendStream* send_stream = AddSendStream();
+  webrtc::FakeVideoReceiveStream* recv_stream = AddRecvStream();
 
   EXPECT_GT(recv_stream->GetConfig().rtp.nack.rtp_history_ms, 0);
   EXPECT_GT(send_stream->GetConfig().rtp.nack.rtp_history_ms, 0);
@@ -3583,7 +3583,7 @@
   ASSERT_TRUE(send_channel_->SetSenderParameters(parameters));
   send_channel_->SetSend(false);
 
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
 
   // No frames entered.
   std::vector<webrtc::VideoStream> streams = stream->GetVideoStreams();
@@ -3591,8 +3591,8 @@
   EXPECT_EQ(0u, streams[0].height);
 
   webrtc::test::FrameForwarder frame_forwarder;
-  cricket::FakeFrameSource frame_source(1280, 720,
-                                        rtc::kNumMicrosecsPerSec / 30);
+  webrtc::FakeFrameSource frame_source(1280, 720,
+                                       rtc::kNumMicrosecsPerSec / 30);
 
   EXPECT_TRUE(
       send_channel_->SetVideoSend(last_ssrc_, nullptr, &frame_forwarder));
@@ -3615,8 +3615,8 @@
   AddSendStream();
 
   webrtc::test::FrameForwarder frame_forwarder;
-  cricket::FakeFrameSource frame_source(1280, 720,
-                                        rtc::kNumMicrosecsPerSec / 30);
+  webrtc::FakeFrameSource frame_source(1280, 720,
+                                       rtc::kNumMicrosecsPerSec / 30);
   VideoOptions min_bitrate_options;
   min_bitrate_options.screencast_min_bitrate_kbps = kScreenshareMinBitrateKbps;
   EXPECT_TRUE(send_channel_->SetVideoSend(last_ssrc_, &min_bitrate_options,
@@ -3626,7 +3626,8 @@
 
   frame_forwarder.IncomingCapturedFrame(frame_source.GetFrame());
   ASSERT_EQ(1u, fake_call_->GetVideoSendStreams().size());
-  FakeVideoSendStream* send_stream = fake_call_->GetVideoSendStreams().front();
+  webrtc::FakeVideoSendStream* send_stream =
+      fake_call_->GetVideoSendStreams().front();
 
   EXPECT_EQ(1, send_stream->GetNumberOfSwappedFrames());
 
@@ -3677,15 +3678,16 @@
   VideoOptions options;
   options.is_screencast = true;
   webrtc::test::FrameForwarder frame_forwarder;
-  cricket::FakeFrameSource frame_source(1280, 720,
-                                        rtc::kNumMicrosecsPerSec / 30);
+  webrtc::FakeFrameSource frame_source(1280, 720,
+                                       rtc::kNumMicrosecsPerSec / 30);
   EXPECT_TRUE(
       send_channel_->SetVideoSend(last_ssrc_, &options, &frame_forwarder));
   EXPECT_TRUE(send_channel_->SetSend(true));
 
   frame_forwarder.IncomingCapturedFrame(frame_source.GetFrame());
   ASSERT_EQ(1u, fake_call_->GetVideoSendStreams().size());
-  FakeVideoSendStream* send_stream = fake_call_->GetVideoSendStreams().front();
+  webrtc::FakeVideoSendStream* send_stream =
+      fake_call_->GetVideoSendStreams().front();
 
   webrtc::VideoEncoderConfig encoder_config =
       send_stream->GetEncoderConfig().Copy();
@@ -3705,7 +3707,7 @@
 }
 
 TEST_F(WebRtcVideoChannelTest, SuspendBelowMinBitrateDisabledByDefault) {
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
   EXPECT_FALSE(stream->GetConfig().suspend_below_min_bitrate);
 }
 
@@ -3722,7 +3724,7 @@
 
   send_channel_->SetSenderParameters(send_parameters_);
 
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
   EXPECT_TRUE(stream->GetConfig().suspend_below_min_bitrate);
 
   media_config.video.suspend_below_min_bitrate = false;
@@ -3740,7 +3742,7 @@
 }
 
 TEST_F(WebRtcVideoChannelTest, Vp8DenoisingEnabledByDefault) {
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
   webrtc::VideoCodecVP8 vp8_settings;
   ASSERT_TRUE(stream->GetVp8Settings(&vp8_settings)) << "No VP8 config set.";
   EXPECT_TRUE(vp8_settings.denoisingOn);
@@ -3754,7 +3756,8 @@
   // Single-stream settings should apply with RTX as well (verifies that we
   // check number of regular SSRCs and not StreamParams::ssrcs which contains
   // both RTX and regular SSRCs).
-  FakeVideoSendStream* stream = SetUpSimulcast(false, /*with_rtx=*/true);
+  webrtc::FakeVideoSendStream* stream =
+      SetUpSimulcast(false, /*with_rtx=*/true);
 
   webrtc::test::FrameForwarder frame_forwarder;
   EXPECT_TRUE(
@@ -3830,7 +3833,8 @@
   // Single-stream settings should apply with RTX as well (verifies that we
   // check number of regular SSRCs and not StreamParams::ssrcs which contains
   // both RTX and regular SSRCs).
-  FakeVideoSendStream* stream = SetUpSimulcast(false, /*with_rtx=*/true);
+  webrtc::FakeVideoSendStream* stream =
+      SetUpSimulcast(false, /*with_rtx=*/true);
   EXPECT_TRUE(
       send_channel_->SetVideoSend(last_ssrc_, nullptr, &frame_forwarder));
   send_channel_->SetSend(true);
@@ -3866,7 +3870,8 @@
   cricket::VideoSenderParameters parameters;
   parameters.codecs.push_back(GetEngineCodec("VP8"));
   ASSERT_TRUE(send_channel_->SetSenderParameters(parameters));
-  FakeVideoSendStream* send_stream = fake_call_->GetVideoSendStreams().front();
+  webrtc::FakeVideoSendStream* send_stream =
+      fake_call_->GetVideoSendStreams().front();
 
   EXPECT_TRUE(
       send_channel_->SetVideoSend(last_ssrc_, &options, &frame_forwarder));
@@ -3899,7 +3904,8 @@
   cricket::VideoSenderParameters parameters;
   parameters.codecs.push_back(GetEngineCodec("VP8"));
   ASSERT_TRUE(send_channel_->SetSenderParameters(parameters));
-  FakeVideoSendStream* send_stream = fake_call_->GetVideoSendStreams().front();
+  webrtc::FakeVideoSendStream* send_stream =
+      fake_call_->GetVideoSendStreams().front();
 
   EXPECT_TRUE(
       send_channel_->SetVideoSend(last_ssrc_, &options, &frame_forwarder));
@@ -3949,7 +3955,8 @@
   parameters.codecs.push_back(GetEngineCodec("VP9"));
   ASSERT_TRUE(send_channel_->SetSenderParameters(parameters));
 
-  FakeVideoSendStream* stream = SetUpSimulcast(false, /*with_rtx=*/false);
+  webrtc::FakeVideoSendStream* stream =
+      SetUpSimulcast(false, /*with_rtx=*/false);
 
   webrtc::test::FrameForwarder frame_forwarder;
   EXPECT_TRUE(
@@ -4046,8 +4053,8 @@
 
   std::vector<uint32_t> ssrcs = MAKE_VECTOR(kSsrcs3);
 
-  FakeVideoSendStream* stream =
-      AddSendStream(CreateSimStreamParams("cname", ssrcs));
+  webrtc::FakeVideoSendStream* stream =
+      AddSendStream(webrtc::CreateSimStreamParams("cname", ssrcs));
 
   webrtc::VideoSendStream::Config config = stream->GetConfig().Copy();
 
@@ -4075,8 +4082,8 @@
 
   std::vector<uint32_t> ssrcs = MAKE_VECTOR(kSsrcs3);
 
-  FakeVideoSendStream* stream =
-      AddSendStream(CreateSimStreamParams("cname", ssrcs));
+  webrtc::FakeVideoSendStream* stream =
+      AddSendStream(webrtc::CreateSimStreamParams("cname", ssrcs));
 
   webrtc::VideoSendStream::Config config = stream->GetConfig().Copy();
 
@@ -4106,8 +4113,8 @@
   const size_t kNumSpatialLayers = 3;
   std::vector<uint32_t> ssrcs = MAKE_VECTOR(kSsrcs3);
 
-  FakeVideoSendStream* stream =
-      AddSendStream(CreateSimStreamParams("cname", ssrcs));
+  webrtc::FakeVideoSendStream* stream =
+      AddSendStream(webrtc::CreateSimStreamParams("cname", ssrcs));
 
   webrtc::RtpParameters parameters =
       send_channel_->GetRtpSendParameters(ssrcs[0]);
@@ -4138,8 +4145,8 @@
 
   std::vector<uint32_t> ssrcs = MAKE_VECTOR(kSsrcs3);
 
-  FakeVideoSendStream* stream =
-      AddSendStream(CreateSimStreamParams("cname", ssrcs));
+  webrtc::FakeVideoSendStream* stream =
+      AddSendStream(webrtc::CreateSimStreamParams("cname", ssrcs));
 
   webrtc::VideoSendStream::Config config = stream->GetConfig().Copy();
 
@@ -4184,8 +4191,8 @@
 
   std::vector<uint32_t> ssrcs = MAKE_VECTOR(kSsrcs3);
 
-  FakeVideoSendStream* stream =
-      AddSendStream(CreateSimStreamParams("cname", ssrcs));
+  webrtc::FakeVideoSendStream* stream =
+      AddSendStream(webrtc::CreateSimStreamParams("cname", ssrcs));
 
   webrtc::VideoSendStream::Config config = stream->GetConfig().Copy();
 
@@ -4235,7 +4242,8 @@
     parameters.codecs.push_back(GetEngineCodec("VP9"));
     ASSERT_TRUE(send_channel_->SetSenderParameters(parameters));
 
-    FakeVideoSendStream* stream = SetUpSimulcast(false, /*with_rtx=*/false);
+    webrtc::FakeVideoSendStream* stream =
+        SetUpSimulcast(false, /*with_rtx=*/false);
 
     webrtc::test::FrameForwarder frame_forwarder;
     EXPECT_TRUE(
@@ -4366,7 +4374,8 @@
   send_channel_->SetVideoSend(last_ssrc_, &camera_options, &frame_forwarder);
 
   ASSERT_EQ(1u, fake_call_->GetVideoSendStreams().size());
-  FakeVideoSendStream* send_stream = fake_call_->GetVideoSendStreams().front();
+  webrtc::FakeVideoSendStream* send_stream =
+      fake_call_->GetVideoSendStreams().front();
 
   EXPECT_TRUE(send_stream->resolution_scaling_enabled());
   // Dont' expect anything on framerate_scaling_enabled, since the default is
@@ -4420,7 +4429,8 @@
 
   EXPECT_TRUE(send_channel_->SetSend(true));
 
-  FakeVideoSendStream* send_stream = fake_call_->GetVideoSendStreams().front();
+  webrtc::FakeVideoSendStream* send_stream =
+      fake_call_->GetVideoSendStreams().front();
   EXPECT_EQ(resolution_scaling_enabled,
             send_stream->resolution_scaling_enabled());
   EXPECT_EQ(fps_scaling_enabled, send_stream->framerate_scaling_enabled());
@@ -4457,7 +4467,8 @@
 
   EXPECT_TRUE(send_channel_->SetSend(true));
 
-  FakeVideoSendStream* send_stream = fake_call_->GetVideoSendStreams().front();
+  webrtc::FakeVideoSendStream* send_stream =
+      fake_call_->GetVideoSendStreams().front();
 
   if (!enable_overuse) {
     EXPECT_FALSE(send_stream->resolution_scaling_enabled());
@@ -4479,8 +4490,8 @@
   static const int kFrameOffsetMs = 20;
   EXPECT_TRUE(receive_channel_->SetReceiverParameters(recv_parameters_));
 
-  FakeVideoReceiveStream* stream = AddRecvStream();
-  cricket::FakeVideoRenderer renderer;
+  webrtc::FakeVideoReceiveStream* stream = AddRecvStream();
+  webrtc::FakeVideoRenderer renderer;
   EXPECT_TRUE(receive_channel_->SetSink(last_ssrc_, &renderer));
 
   webrtc::VideoFrame video_frame =
@@ -4528,8 +4539,8 @@
   // Using a RTX setup to verify that the default RTX payload type is good.
   const std::vector<uint32_t> ssrcs = MAKE_VECTOR(kSsrcs1);
   const std::vector<uint32_t> rtx_ssrcs = MAKE_VECTOR(kRtxSsrcs1);
-  FakeVideoSendStream* stream = AddSendStream(
-      cricket::CreateSimWithRtxStreamParams("cname", ssrcs, rtx_ssrcs));
+  webrtc::FakeVideoSendStream* stream = AddSendStream(
+      webrtc::CreateSimWithRtxStreamParams("cname", ssrcs, rtx_ssrcs));
   webrtc::VideoSendStream::Config config = stream->GetConfig().Copy();
 
   // Make sure NACK and FEC are enabled on the correct payload types.
@@ -4548,7 +4559,7 @@
   parameters.codecs.push_back(GetEngineCodec("VP8"));
   EXPECT_TRUE(send_channel_->SetSenderParameters(parameters));
 
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
   const webrtc::VideoSendStream::Config config = stream->GetConfig().Copy();
   EXPECT_FALSE(config.rtp.raw_payload);
 }
@@ -4559,7 +4570,7 @@
   parameters.codecs.back().packetization = kPacketizationParamRaw;
   EXPECT_TRUE(send_channel_->SetSenderParameters(parameters));
 
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
   const webrtc::VideoSendStream::Config config = stream->GetConfig().Copy();
   EXPECT_TRUE(config.rtp.raw_payload);
 }
@@ -4569,7 +4580,7 @@
 // TODO(brandtr): Remove or update these tests when FlexFEC _is_ enabled by
 // default.
 TEST_F(WebRtcVideoChannelTest, FlexfecSendCodecWithoutSsrcNotExposedByDefault) {
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
   webrtc::VideoSendStream::Config config = stream->GetConfig().Copy();
 
   EXPECT_EQ(-1, config.rtp.flexfec.payload_type);
@@ -4578,8 +4589,9 @@
 }
 
 TEST_F(WebRtcVideoChannelTest, FlexfecSendCodecWithSsrcNotExposedByDefault) {
-  FakeVideoSendStream* stream = AddSendStream(
-      CreatePrimaryWithFecFrStreamParams("cname", kSsrcs1[0], kFlexfecSsrc));
+  webrtc::FakeVideoSendStream* stream =
+      AddSendStream(webrtc::CreatePrimaryWithFecFrStreamParams(
+          "cname", kSsrcs1[0], kFlexfecSsrc));
   webrtc::VideoSendStream::Config config = stream->GetConfig().Copy();
 
   EXPECT_EQ(-1, config.rtp.flexfec.payload_type);
@@ -4590,16 +4602,16 @@
 TEST_F(WebRtcVideoChannelTest, FlexfecRecvCodecWithoutSsrcNotExposedByDefault) {
   AddRecvStream();
 
-  const std::vector<FakeFlexfecReceiveStream*>& streams =
+  const std::vector<webrtc::FakeFlexfecReceiveStream*>& streams =
       fake_call_->GetFlexfecReceiveStreams();
   EXPECT_TRUE(streams.empty());
 }
 
 TEST_F(WebRtcVideoChannelTest, FlexfecRecvCodecWithSsrcExposedByDefault) {
-  AddRecvStream(
-      CreatePrimaryWithFecFrStreamParams("cname", kSsrcs1[0], kFlexfecSsrc));
+  AddRecvStream(webrtc::CreatePrimaryWithFecFrStreamParams("cname", kSsrcs1[0],
+                                                           kFlexfecSsrc));
 
-  const std::vector<FakeFlexfecReceiveStream*>& streams =
+  const std::vector<webrtc::FakeFlexfecReceiveStream*>& streams =
       fake_call_->GetFlexfecReceiveStreams();
   EXPECT_EQ(1U, streams.size());
 }
@@ -4621,14 +4633,14 @@
 TEST_F(WebRtcVideoChannelFlexfecRecvTest, SetDefaultRecvCodecsWithoutSsrc) {
   AddRecvStream();
 
-  const std::vector<FakeFlexfecReceiveStream*>& streams =
+  const std::vector<webrtc::FakeFlexfecReceiveStream*>& streams =
       fake_call_->GetFlexfecReceiveStreams();
   EXPECT_TRUE(streams.empty());
 
-  const std::vector<FakeVideoReceiveStream*>& video_streams =
+  const std::vector<webrtc::FakeVideoReceiveStream*>& video_streams =
       fake_call_->GetVideoReceiveStreams();
   ASSERT_EQ(1U, video_streams.size());
-  const FakeVideoReceiveStream& video_stream = *video_streams.front();
+  const webrtc::FakeVideoReceiveStream& video_stream = *video_streams.front();
   const webrtc::VideoReceiveStreamInterface::Config& video_config =
       video_stream.GetConfig();
   EXPECT_FALSE(video_config.rtp.protected_by_flexfec);
@@ -4636,10 +4648,10 @@
 }
 
 TEST_F(WebRtcVideoChannelFlexfecRecvTest, SetDefaultRecvCodecsWithSsrc) {
-  AddRecvStream(
-      CreatePrimaryWithFecFrStreamParams("cname", kSsrcs1[0], kFlexfecSsrc));
+  AddRecvStream(webrtc::CreatePrimaryWithFecFrStreamParams("cname", kSsrcs1[0],
+                                                           kFlexfecSsrc));
 
-  const std::vector<FakeFlexfecReceiveStream*>& streams =
+  const std::vector<webrtc::FakeFlexfecReceiveStream*>& streams =
       fake_call_->GetFlexfecReceiveStreams();
   ASSERT_EQ(1U, streams.size());
   const auto* stream = streams.front();
@@ -4649,10 +4661,10 @@
   ASSERT_EQ(1U, config.protected_media_ssrcs.size());
   EXPECT_EQ(kSsrcs1[0], config.protected_media_ssrcs[0]);
 
-  const std::vector<FakeVideoReceiveStream*>& video_streams =
+  const std::vector<webrtc::FakeVideoReceiveStream*>& video_streams =
       fake_call_->GetVideoReceiveStreams();
   ASSERT_EQ(1U, video_streams.size());
-  const FakeVideoReceiveStream& video_stream = *video_streams.front();
+  const webrtc::FakeVideoReceiveStream& video_stream = *video_streams.front();
   const webrtc::VideoReceiveStreamInterface::Config& video_config =
       video_stream.GetConfig();
   EXPECT_TRUE(video_config.rtp.protected_by_flexfec);
@@ -4669,13 +4681,13 @@
   recv_parameters.codecs.push_back(GetEngineCodec("VP8"));
   ASSERT_TRUE(receive_channel_->SetReceiverParameters(recv_parameters));
 
-  AddRecvStream(
-      CreatePrimaryWithFecFrStreamParams("cname", kSsrcs1[0], kFlexfecSsrc));
+  AddRecvStream(webrtc::CreatePrimaryWithFecFrStreamParams("cname", kSsrcs1[0],
+                                                           kFlexfecSsrc));
   EXPECT_EQ(1, fake_call_->GetNumCreatedReceiveStreams());
-  const std::vector<FakeVideoReceiveStream*>& video_streams =
+  const std::vector<webrtc::FakeVideoReceiveStream*>& video_streams =
       fake_call_->GetVideoReceiveStreams();
   ASSERT_EQ(1U, video_streams.size());
-  const FakeVideoReceiveStream* video_stream = video_streams.front();
+  const webrtc::FakeVideoReceiveStream* video_stream = video_streams.front();
   const webrtc::VideoReceiveStreamInterface::Config* video_config =
       &video_stream->GetConfig();
   EXPECT_FALSE(video_config->rtp.protected_by_flexfec);
@@ -4711,14 +4723,14 @@
   recv_parameters.codecs.push_back(GetEngineCodec("flexfec-03"));
   ASSERT_TRUE(receive_channel_->SetReceiverParameters(recv_parameters));
 
-  AddRecvStream(
-      CreatePrimaryWithFecFrStreamParams("cname", kSsrcs1[0], kFlexfecSsrc));
+  AddRecvStream(webrtc::CreatePrimaryWithFecFrStreamParams("cname", kSsrcs1[0],
+                                                           kFlexfecSsrc));
   EXPECT_EQ(2, fake_call_->GetNumCreatedReceiveStreams());
   EXPECT_EQ(1U, fake_call_->GetFlexfecReceiveStreams().size());
-  const std::vector<FakeVideoReceiveStream*>& video_streams =
+  const std::vector<webrtc::FakeVideoReceiveStream*>& video_streams =
       fake_call_->GetVideoReceiveStreams();
   ASSERT_EQ(1U, video_streams.size());
-  const FakeVideoReceiveStream* video_stream = video_streams.front();
+  const webrtc::FakeVideoReceiveStream* video_stream = video_streams.front();
   const webrtc::VideoReceiveStreamInterface::Config* video_config =
       &video_stream->GetConfig();
   EXPECT_TRUE(video_config->rtp.protected_by_flexfec);
@@ -4754,10 +4766,10 @@
   recv_parameters.codecs.push_back(duplicate);
   ASSERT_TRUE(receive_channel_->SetReceiverParameters(recv_parameters));
 
-  AddRecvStream(
-      CreatePrimaryWithFecFrStreamParams("cname", kSsrcs1[0], kFlexfecSsrc));
+  AddRecvStream(webrtc::CreatePrimaryWithFecFrStreamParams("cname", kSsrcs1[0],
+                                                           kFlexfecSsrc));
 
-  const std::vector<FakeFlexfecReceiveStream*>& streams =
+  const std::vector<webrtc::FakeFlexfecReceiveStream*>& streams =
       fake_call_->GetFlexfecReceiveStreams();
   ASSERT_EQ(1U, streams.size());
   const auto* stream = streams.front();
@@ -4777,7 +4789,7 @@
 };
 
 TEST_F(WebRtcVideoChannelFlexfecSendRecvTest, SetDefaultSendCodecsWithoutSsrc) {
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
   webrtc::VideoSendStream::Config config = stream->GetConfig().Copy();
 
   EXPECT_EQ(GetEngineCodec("flexfec-03").id, config.rtp.flexfec.payload_type);
@@ -4786,8 +4798,9 @@
 }
 
 TEST_F(WebRtcVideoChannelFlexfecSendRecvTest, SetDefaultSendCodecsWithSsrc) {
-  FakeVideoSendStream* stream = AddSendStream(
-      CreatePrimaryWithFecFrStreamParams("cname", kSsrcs1[0], kFlexfecSsrc));
+  webrtc::FakeVideoSendStream* stream =
+      AddSendStream(webrtc::CreatePrimaryWithFecFrStreamParams(
+          "cname", kSsrcs1[0], kFlexfecSsrc));
   webrtc::VideoSendStream::Config config = stream->GetConfig().Copy();
 
   EXPECT_EQ(GetEngineCodec("flexfec-03").id, config.rtp.flexfec.payload_type);
@@ -4801,7 +4814,7 @@
   parameters.codecs.push_back(GetEngineCodec("VP8"));
   ASSERT_TRUE(send_channel_->SetSenderParameters(parameters));
 
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
   webrtc::VideoSendStream::Config config = stream->GetConfig().Copy();
 
   EXPECT_EQ(-1, config.rtp.ulpfec.ulpfec_payload_type);
@@ -4813,25 +4826,26 @@
   parameters.codecs.push_back(GetEngineCodec("VP8"));
   ASSERT_TRUE(send_channel_->SetSenderParameters(parameters));
 
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
   webrtc::VideoSendStream::Config config = stream->GetConfig().Copy();
 
   EXPECT_EQ(-1, config.rtp.flexfec.payload_type);
 }
 
 TEST_F(WebRtcVideoChannelFlexfecRecvTest, SetRecvCodecsWithFec) {
-  AddRecvStream(
-      CreatePrimaryWithFecFrStreamParams("cname", kSsrcs1[0], kFlexfecSsrc));
+  AddRecvStream(webrtc::CreatePrimaryWithFecFrStreamParams("cname", kSsrcs1[0],
+                                                           kFlexfecSsrc));
 
   cricket::VideoReceiverParameters recv_parameters;
   recv_parameters.codecs.push_back(GetEngineCodec("VP8"));
   recv_parameters.codecs.push_back(GetEngineCodec("flexfec-03"));
   ASSERT_TRUE(receive_channel_->SetReceiverParameters(recv_parameters));
 
-  const std::vector<FakeFlexfecReceiveStream*>& flexfec_streams =
+  const std::vector<webrtc::FakeFlexfecReceiveStream*>& flexfec_streams =
       fake_call_->GetFlexfecReceiveStreams();
   ASSERT_EQ(1U, flexfec_streams.size());
-  const FakeFlexfecReceiveStream* flexfec_stream = flexfec_streams.front();
+  const webrtc::FakeFlexfecReceiveStream* flexfec_stream =
+      flexfec_streams.front();
   const webrtc::FlexfecReceiveStream::Config& flexfec_stream_config =
       flexfec_stream->GetConfig();
   EXPECT_EQ(GetEngineCodec("flexfec-03").id,
@@ -4839,9 +4853,9 @@
   EXPECT_EQ(kFlexfecSsrc, flexfec_stream_config.rtp.remote_ssrc);
   ASSERT_EQ(1U, flexfec_stream_config.protected_media_ssrcs.size());
   EXPECT_EQ(kSsrcs1[0], flexfec_stream_config.protected_media_ssrcs[0]);
-  const std::vector<FakeVideoReceiveStream*>& video_streams =
+  const std::vector<webrtc::FakeVideoReceiveStream*>& video_streams =
       fake_call_->GetVideoReceiveStreams();
-  const FakeVideoReceiveStream* video_stream = video_streams.front();
+  const webrtc::FakeVideoReceiveStream* video_stream = video_streams.front();
   const webrtc::VideoReceiveStreamInterface::Config& video_stream_config =
       video_stream->GetConfig();
   EXPECT_EQ(video_stream_config.rtp.local_ssrc,
@@ -4862,7 +4876,7 @@
   parameters.codecs.push_back(GetEngineCodec("flexfec-03"));
   ASSERT_TRUE(send_channel_->SetSenderParameters(parameters));
 
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
   webrtc::VideoSendStream::Config config = stream->GetConfig().Copy();
 
   EXPECT_EQ(-1, config.rtp.flexfec.payload_type);
@@ -4877,8 +4891,9 @@
   parameters.codecs.push_back(GetEngineCodec("flexfec-03"));
   ASSERT_TRUE(send_channel_->SetSenderParameters(parameters));
 
-  FakeVideoSendStream* stream = AddSendStream(
-      CreatePrimaryWithFecFrStreamParams("cname", kSsrcs1[0], kFlexfecSsrc));
+  webrtc::FakeVideoSendStream* stream =
+      AddSendStream(webrtc::CreatePrimaryWithFecFrStreamParams(
+          "cname", kSsrcs1[0], kFlexfecSsrc));
   webrtc::VideoSendStream::Config config = stream->GetConfig().Copy();
 
   EXPECT_EQ(-1, config.rtp.flexfec.payload_type);
@@ -4968,7 +4983,7 @@
   parameters.codecs.push_back(GetEngineCodec("ulpfec"));
   ASSERT_TRUE(send_channel_->SetSenderParameters(parameters));
 
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
   webrtc::VideoSendStream::Config config = stream->GetConfig().Copy();
 
   EXPECT_EQ(GetEngineCodec("ulpfec").id, config.rtp.ulpfec.ulpfec_payload_type);
@@ -4989,8 +5004,9 @@
   parameters.codecs.push_back(GetEngineCodec("flexfec-03"));
   ASSERT_TRUE(send_channel_->SetSenderParameters(parameters));
 
-  FakeVideoSendStream* stream = AddSendStream(
-      CreatePrimaryWithFecFrStreamParams("cname", kSsrcs1[0], kFlexfecSsrc));
+  webrtc::FakeVideoSendStream* stream =
+      AddSendStream(webrtc::CreatePrimaryWithFecFrStreamParams(
+          "cname", kSsrcs1[0], kFlexfecSsrc));
   webrtc::VideoSendStream::Config config = stream->GetConfig().Copy();
 
   EXPECT_EQ(GetEngineCodec("flexfec-03").id, config.rtp.flexfec.payload_type);
@@ -5016,7 +5032,7 @@
   ASSERT_TRUE(send_channel_->SetSenderParameters(parameters));
   send_channel_->SetSend(true);
 
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
   webrtc::test::FrameForwarder frame_forwarder;
   EXPECT_TRUE(
       send_channel_->SetVideoSend(last_ssrc_, nullptr, &frame_forwarder));
@@ -5144,7 +5160,7 @@
 
 TEST_F(WebRtcVideoChannelTest, SetMaxSendBandwidthAndAddSendStream) {
   send_parameters_.max_bandwidth_bps = 99999;
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
   ExpectSetMaxBitrate(send_parameters_.max_bandwidth_bps);
   ASSERT_TRUE(send_channel_->SetSenderParameters(send_parameters_));
   ASSERT_EQ(1u, stream->GetVideoStreams().size());
@@ -5171,9 +5187,10 @@
   ExpectSetMaxBitrate(300000);
   ASSERT_TRUE(send_channel_->SetSenderParameters(send_parameters_));
 
-  std::vector<FakeVideoSendStream*> video_send_streams = GetFakeSendStreams();
+  std::vector<webrtc::FakeVideoSendStream*> video_send_streams =
+      GetFakeSendStreams();
   ASSERT_EQ(1u, video_send_streams.size());
-  FakeVideoSendStream* video_send_stream = video_send_streams[0];
+  webrtc::FakeVideoSendStream* video_send_stream = video_send_streams[0];
   ASSERT_EQ(1u, video_send_streams[0]->GetVideoStreams().size());
   // First the max bitrate is set based upon the codec param.
   EXPECT_EQ(300000,
@@ -5200,9 +5217,10 @@
   ExpectSetMaxBitrate(300000);
   ASSERT_TRUE(send_channel_->SetSenderParameters(send_parameters_));
 
-  std::vector<FakeVideoSendStream*> video_send_streams = GetFakeSendStreams();
+  std::vector<webrtc::FakeVideoSendStream*> video_send_streams =
+      GetFakeSendStreams();
   ASSERT_EQ(1u, video_send_streams.size());
-  FakeVideoSendStream* video_send_stream = video_send_streams[0];
+  webrtc::FakeVideoSendStream* video_send_stream = video_send_streams[0];
   ASSERT_EQ(1u, video_send_stream->GetVideoStreams().size());
   // First the max bitrate is set based upon the codec param.
   EXPECT_EQ(300000, video_send_stream->GetVideoStreams()[0].max_bitrate_bps);
@@ -5221,7 +5239,7 @@
 TEST_F(WebRtcVideoChannelTest,
        MaxBitrateIsMinimumOfMaxSendBandwidthAndMaxEncodingBitrate) {
   send_parameters_.max_bandwidth_bps = 99999;
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
   ExpectSetMaxBitrate(send_parameters_.max_bandwidth_bps);
   ASSERT_TRUE(send_channel_->SetSenderParameters(send_parameters_));
   ASSERT_EQ(1u, stream->GetVideoStreams().size());
@@ -5250,7 +5268,7 @@
   ASSERT_TRUE(send_channel_->SetSenderParameters(parameters));
   send_channel_->SetSend(true);
 
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
 
   webrtc::test::FrameForwarder frame_forwarder;
   EXPECT_TRUE(
@@ -5276,8 +5294,8 @@
   ASSERT_TRUE(send_channel_->SetSenderParameters(parameters));
   send_channel_->SetSend(true);
 
-  FakeVideoSendStream* stream = AddSendStream(
-      cricket::CreateSimStreamParams("cname", MAKE_VECTOR(kSsrcs3)));
+  webrtc::FakeVideoSendStream* stream = AddSendStream(
+      webrtc::CreateSimStreamParams("cname", MAKE_VECTOR(kSsrcs3)));
 
   // Send a frame to make sure this scales up to >1 stream (simulcast).
   webrtc::test::FrameForwarder frame_forwarder;
@@ -5444,7 +5462,7 @@
       kSecondUlpfecPayloadType, cricket::kUlpfecCodecName));
   ASSERT_TRUE(receive_channel_->SetReceiverParameters(parameters));
 
-  FakeVideoReceiveStream* recv_stream = AddRecvStream();
+  webrtc::FakeVideoReceiveStream* recv_stream = AddRecvStream();
   EXPECT_EQ(kFirstUlpfecPayloadType,
             recv_stream->GetConfig().rtp.ulpfec_payload_type);
 }
@@ -5461,7 +5479,7 @@
       cricket::CreateVideoCodec(kSecondRedPayloadType, cricket::kRedCodecName));
   ASSERT_TRUE(receive_channel_->SetReceiverParameters(parameters));
 
-  FakeVideoReceiveStream* recv_stream = AddRecvStream();
+  webrtc::FakeVideoReceiveStream* recv_stream = AddRecvStream();
   EXPECT_EQ(kFirstRedPayloadType,
             recv_stream->GetConfig().rtp.red_payload_type);
 }
@@ -5593,7 +5611,7 @@
   parameters.codecs = engine_.LegacyRecvCodecs();
   EXPECT_TRUE(receive_channel_->SetReceiverParameters(parameters));
 
-  FakeVideoReceiveStream* stream = AddRecvStream();
+  webrtc::FakeVideoReceiveStream* stream = AddRecvStream();
   const webrtc::VideoReceiveStreamInterface::Config& config =
       stream->GetConfig();
   EXPECT_EQ(engine_.LegacyRecvCodecs()[0].name,
@@ -5622,7 +5640,7 @@
   send_parameters.codecs.push_back(GetEngineCodec("ulpfec"));
   ASSERT_TRUE(send_channel_->SetSenderParameters(send_parameters));
 
-  FakeVideoReceiveStream* stream = AddRecvStream();
+  webrtc::FakeVideoReceiveStream* stream = AddRecvStream();
 
   EXPECT_EQ(GetEngineCodec("ulpfec").id,
             stream->GetConfig().rtp.ulpfec_payload_type);
@@ -5637,13 +5655,13 @@
 }
 
 TEST_F(WebRtcVideoChannelFlexfecRecvTest, SetRecvParamsWithoutFecDisablesFec) {
-  AddRecvStream(
-      CreatePrimaryWithFecFrStreamParams("cname", kSsrcs1[0], kFlexfecSsrc));
-  const std::vector<FakeFlexfecReceiveStream*>& streams =
+  AddRecvStream(webrtc::CreatePrimaryWithFecFrStreamParams("cname", kSsrcs1[0],
+                                                           kFlexfecSsrc));
+  const std::vector<webrtc::FakeFlexfecReceiveStream*>& streams =
       fake_call_->GetFlexfecReceiveStreams();
 
   ASSERT_EQ(1U, streams.size());
-  const FakeFlexfecReceiveStream* stream = streams.front();
+  const webrtc::FakeFlexfecReceiveStream* stream = streams.front();
   EXPECT_EQ(GetEngineCodec("flexfec-03").id, stream->GetConfig().payload_type);
   EXPECT_EQ(kFlexfecSsrc, stream->remote_ssrc());
   ASSERT_EQ(1U, stream->GetConfig().protected_media_ssrcs.size());
@@ -5657,7 +5675,7 @@
 }
 
 TEST_F(WebRtcVideoChannelTest, SetSendParamsWithFecEnablesFec) {
-  FakeVideoReceiveStream* stream = AddRecvStream();
+  webrtc::FakeVideoReceiveStream* stream = AddRecvStream();
   EXPECT_EQ(GetEngineCodec("ulpfec").id,
             stream->GetConfig().rtp.ulpfec_payload_type);
 
@@ -5685,9 +5703,9 @@
 
 TEST_F(WebRtcVideoChannelFlexfecSendRecvTest,
        SetSendRecvParamsWithFecEnablesFec) {
-  AddRecvStream(
-      CreatePrimaryWithFecFrStreamParams("cname", kSsrcs1[0], kFlexfecSsrc));
-  const std::vector<FakeFlexfecReceiveStream*>& streams =
+  AddRecvStream(webrtc::CreatePrimaryWithFecFrStreamParams("cname", kSsrcs1[0],
+                                                           kFlexfecSsrc));
+  const std::vector<webrtc::FakeFlexfecReceiveStream*>& streams =
       fake_call_->GetFlexfecReceiveStreams();
 
   cricket::VideoReceiverParameters recv_parameters;
@@ -5695,7 +5713,8 @@
   recv_parameters.codecs.push_back(GetEngineCodec("flexfec-03"));
   ASSERT_TRUE(receive_channel_->SetReceiverParameters(recv_parameters));
   ASSERT_EQ(1U, streams.size());
-  const FakeFlexfecReceiveStream* stream_with_recv_params = streams.front();
+  const webrtc::FakeFlexfecReceiveStream* stream_with_recv_params =
+      streams.front();
   EXPECT_EQ(GetEngineCodec("flexfec-03").id,
             stream_with_recv_params->GetConfig().payload_type);
   EXPECT_EQ(kFlexfecSsrc, stream_with_recv_params->GetConfig().rtp.remote_ssrc);
@@ -5709,7 +5728,8 @@
   send_parameters.codecs.push_back(GetEngineCodec("flexfec-03"));
   ASSERT_TRUE(send_channel_->SetSenderParameters(send_parameters));
   ASSERT_EQ(1U, streams.size());
-  const FakeFlexfecReceiveStream* stream_with_send_params = streams.front();
+  const webrtc::FakeFlexfecReceiveStream* stream_with_send_params =
+      streams.front();
   EXPECT_EQ(GetEngineCodec("flexfec-03").id,
             stream_with_send_params->GetConfig().payload_type);
   EXPECT_EQ(kFlexfecSsrc, stream_with_send_params->GetConfig().rtp.remote_ssrc);
@@ -5781,7 +5801,7 @@
 }
 
 TEST_F(WebRtcVideoChannelTest, SetSend) {
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
   EXPECT_FALSE(stream->IsSending());
 
   // false->true
@@ -5798,15 +5818,15 @@
   EXPECT_FALSE(stream->IsSending());
 
   EXPECT_TRUE(send_channel_->SetSend(true));
-  FakeVideoSendStream* new_stream = AddSendStream();
+  webrtc::FakeVideoSendStream* new_stream = AddSendStream();
   EXPECT_TRUE(new_stream->IsSending())
       << "Send stream created after SetSend(true) not sending initially.";
 }
 
 // This test verifies DSCP settings are properly applied on video media channel.
 TEST_F(WebRtcVideoChannelTest, TestSetDscpOptions) {
-  std::unique_ptr<cricket::FakeNetworkInterface> network_interface(
-      new cricket::FakeNetworkInterface);
+  std::unique_ptr<webrtc::FakeNetworkInterface> network_interface(
+      new webrtc::FakeNetworkInterface);
   MediaConfig config;
   std::unique_ptr<cricket::VideoMediaSendChannelInterface> send_channel;
   webrtc::RtpParameters parameters;
@@ -5865,7 +5885,7 @@
 // send video streams.
 TEST_F(WebRtcVideoChannelTest, TestSetSendRtcpReducedSize) {
   // Create stream, expecting that default mode is "compound".
-  FakeVideoSendStream* stream1 = AddSendStream();
+  webrtc::FakeVideoSendStream* stream1 = AddSendStream();
   EXPECT_EQ(webrtc::RtcpMode::kCompound, stream1->GetConfig().rtp.rtcp_mode);
   webrtc::RtpParameters rtp_parameters =
       send_channel_->GetRtpSendParameters(last_ssrc_);
@@ -5880,7 +5900,7 @@
   EXPECT_TRUE(rtp_parameters.rtcp.reduced_size);
 
   // Create a new stream and ensure it picks up the reduced size mode.
-  FakeVideoSendStream* stream2 = AddSendStream();
+  webrtc::FakeVideoSendStream* stream2 = AddSendStream();
   EXPECT_EQ(webrtc::RtcpMode::kReducedSize, stream2->GetConfig().rtp.rtcp_mode);
 }
 
@@ -5888,7 +5908,7 @@
 // receive video streams.
 TEST_F(WebRtcVideoChannelTest, TestSetRecvRtcpReducedSize) {
   // Create stream, expecting that default mode is "compound".
-  FakeVideoReceiveStream* stream1 = AddRecvStream();
+  webrtc::FakeVideoReceiveStream* stream1 = AddRecvStream();
   EXPECT_EQ(webrtc::RtcpMode::kCompound, stream1->GetConfig().rtp.rtcp_mode);
 
   // Now enable reduced size mode.
@@ -5900,7 +5920,7 @@
   EXPECT_EQ(webrtc::RtcpMode::kReducedSize, stream1->GetConfig().rtp.rtcp_mode);
 
   // Create a new stream and ensure it picks up the reduced size mode.
-  FakeVideoReceiveStream* stream2 = AddRecvStream();
+  webrtc::FakeVideoReceiveStream* stream2 = AddRecvStream();
   EXPECT_EQ(webrtc::RtcpMode::kReducedSize, stream2->GetConfig().rtp.rtcp_mode);
 }
 
@@ -5939,7 +5959,7 @@
 }
 
 TEST_F(WebRtcVideoChannelTest, GetStatsReportsEncoderImplementationName) {
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
   webrtc::VideoSendStream::Stats stats;
   stats.encoder_implementation_name = "encoder_implementation_name";
   stream->SetStats(stats);
@@ -5954,7 +5974,7 @@
 }
 
 TEST_F(WebRtcVideoChannelTest, GetStatsReportsPowerEfficientEncoder) {
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
   webrtc::VideoSendStream::Stats stats;
   stats.power_efficient_encoder = true;
   stream->SetStats(stats);
@@ -5968,7 +5988,7 @@
 }
 
 TEST_F(WebRtcVideoChannelTest, GetStatsReportsCpuOveruseMetrics) {
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
   webrtc::VideoSendStream::Stats stats;
   stats.avg_encode_time_ms = 13;
   stats.encode_usage_percent = 42;
@@ -5985,7 +6005,7 @@
 }
 
 TEST_F(WebRtcVideoChannelTest, GetStatsReportsFramesEncoded) {
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
   webrtc::VideoSendStream::Stats stats;
   stats.frames_encoded = 13;
   stream->SetStats(stats);
@@ -5999,7 +6019,7 @@
 }
 
 TEST_F(WebRtcVideoChannelTest, GetStatsReportsKeyFramesEncoded) {
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
   webrtc::VideoSendStream::Stats stats;
   stats.substreams[123].frame_counts.key_frames = 10;
   stats.substreams[456].frame_counts.key_frames = 87;
@@ -6017,7 +6037,7 @@
 }
 
 TEST_F(WebRtcVideoChannelTest, GetStatsReportsPerLayerQpSum) {
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
   webrtc::VideoSendStream::Stats stats;
   stats.substreams[123].qp_sum = 15;
   stats.substreams[456].qp_sum = 11;
@@ -6072,7 +6092,7 @@
 }
 
 TEST_F(WebRtcVideoChannelTest, GetAggregatedStatsReportWithoutSubStreams) {
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
   auto stats = GetInitialisedStats();
   stream->SetStats(stats);
   cricket::VideoMediaSendInfo send_info;
@@ -6146,7 +6166,7 @@
 }
 
 TEST_F(WebRtcVideoChannelTest, GetAggregatedStatsReportForSubStreams) {
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
   auto stats = GetInitialisedStats();
 
   const uint32_t ssrc_1 = 123u;
@@ -6271,7 +6291,7 @@
 }
 
 TEST_F(WebRtcVideoChannelTest, GetPerLayerStatsReportForSubStreams) {
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
   auto stats = GetInitialisedStats();
 
   const uint32_t ssrc_1 = 123u;
@@ -6403,8 +6423,8 @@
 
   // Create simulcast stream from both SSRCs.
   // `kSsrc1` is the "main" ssrc used for getting parameters.
-  FakeVideoSendStream* stream =
-      AddSendStream(cricket::CreateSimStreamParams("cname", {kSsrc1, kSsrc2}));
+  webrtc::FakeVideoSendStream* stream =
+      AddSendStream(webrtc::CreateSimStreamParams("cname", {kSsrc1, kSsrc2}));
 
   webrtc::RtpParameters parameters =
       send_channel_->GetRtpSendParameters(kSsrc1);
@@ -6444,8 +6464,8 @@
   // Configuring SVC is done the same way that simulcast is configured, the only
   // difference is that the VP9 codec is used. This triggers special hacks that
   // we depend on because we don't have a proper SVC API yet.
-  FakeVideoSendStream* stream = AddSendStream(
-      cricket::CreateSimStreamParams("cname", {kSsrc1, kSsrc2, kSsrc3}));
+  webrtc::FakeVideoSendStream* stream = AddSendStream(
+      webrtc::CreateSimStreamParams("cname", {kSsrc1, kSsrc2, kSsrc3}));
   // Expect that we got SVC.
   EXPECT_EQ(stream->GetEncoderConfig().number_of_streams, 1u);
   webrtc::VideoCodecVP9 vp9_settings;
@@ -6492,7 +6512,7 @@
 }
 
 TEST_F(WebRtcVideoChannelTest, MediaSubstreamMissingProducesEmpyStats) {
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
 
   const uint32_t kRtxSsrc = 123u;
   const uint32_t kMissingMediaSsrc = 124u;
@@ -6516,7 +6536,7 @@
 }
 
 TEST_F(WebRtcVideoChannelTest, GetStatsReportsUpperResolution) {
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
   webrtc::VideoSendStream::Stats stats;
   stats.substreams[17].width = 123;
   stats.substreams[17].height = 40;
@@ -6544,7 +6564,7 @@
 }
 
 TEST_F(WebRtcVideoChannelTest, GetStatsReportsCpuAdaptationStats) {
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
   webrtc::VideoSendStream::Stats stats;
   stats.number_of_cpu_adapt_changes = 2;
   stats.cpu_limited_resolution = true;
@@ -6563,7 +6583,7 @@
 }
 
 TEST_F(WebRtcVideoChannelTest, GetStatsReportsAdaptationAndBandwidthStats) {
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
   webrtc::VideoSendStream::Stats stats;
   stats.number_of_cpu_adapt_changes = 2;
   stats.cpu_limited_resolution = true;
@@ -6684,7 +6704,7 @@
 
 TEST_F(WebRtcVideoChannelTest,
        GetStatsReportsTransmittedAndRetransmittedBytesAndPacketsCorrectly) {
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
   webrtc::VideoSendStream::Stats stats;
   // Simulcast layer 1, RTP stream. header+padding=10, payload=20, packets=3.
   stats.substreams[101].type =
@@ -6766,7 +6786,7 @@
 
 TEST_F(WebRtcVideoChannelTest,
        GetStatsTranslatesBandwidthLimitedResolutionCorrectly) {
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
   webrtc::VideoSendStream::Stats stats;
   stats.bw_limited_resolution = true;
   stream->SetStats(stats);
@@ -6782,7 +6802,7 @@
 }
 
 TEST_F(WebRtcVideoChannelTest, GetStatsTranslatesSendRtcpPacketTypesCorrectly) {
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
   webrtc::VideoSendStream::Stats stats;
   stats.substreams[17].rtcp_packet_type_counts.fir_packets = 2;
   stats.substreams[17].rtcp_packet_type_counts.nack_packets = 3;
@@ -6814,7 +6834,7 @@
 
 TEST_F(WebRtcVideoChannelTest,
        GetStatsTranslatesReceiveRtcpPacketTypesCorrectly) {
-  FakeVideoReceiveStream* stream = AddRecvStream();
+  webrtc::FakeVideoReceiveStream* stream = AddRecvStream();
   webrtc::VideoReceiveStreamInterface::Stats stats;
   stats.rtcp_packet_type_counts.fir_packets = 2;
   stats.rtcp_packet_type_counts.nack_packets = 3;
@@ -6837,7 +6857,7 @@
 }
 
 TEST_F(WebRtcVideoChannelTest, GetStatsTranslatesDecodeStatsCorrectly) {
-  FakeVideoReceiveStream* stream = AddRecvStream();
+  webrtc::FakeVideoReceiveStream* stream = AddRecvStream();
   webrtc::VideoReceiveStreamInterface::Stats stats;
   stats.decoder_implementation_name = "decoder_implementation_name";
   stats.decode_ms = 2;
@@ -6925,7 +6945,7 @@
 
 TEST_F(WebRtcVideoChannelTest,
        GetStatsTranslatesInterFrameDelayStatsCorrectly) {
-  FakeVideoReceiveStream* stream = AddRecvStream();
+  webrtc::FakeVideoReceiveStream* stream = AddRecvStream();
   webrtc::VideoReceiveStreamInterface::Stats stats;
   stats.total_inter_frame_delay = 0.123;
   stats.total_squared_inter_frame_delay = 0.00456;
@@ -6943,7 +6963,7 @@
 }
 
 TEST_F(WebRtcVideoChannelTest, GetStatsTranslatesReceivePacketStatsCorrectly) {
-  FakeVideoReceiveStream* stream = AddRecvStream();
+  webrtc::FakeVideoReceiveStream* stream = AddRecvStream();
   webrtc::VideoReceiveStreamInterface::Stats stats;
   stats.rtp_stats.packet_counter.payload_bytes = 2;
   stats.rtp_stats.packet_counter.header_bytes = 3;
@@ -6985,7 +7005,7 @@
 }
 
 TEST_F(WebRtcVideoChannelTest, TranslatesSenderBitrateStatsCorrectly) {
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
   webrtc::VideoSendStream::Stats stats;
   stats.target_media_bitrate_bps = 156;
   stats.media_bitrate_bps = 123;
@@ -6995,7 +7015,7 @@
   stats.substreams[42].retransmit_bitrate_bps = 4;
   stream->SetStats(stats);
 
-  FakeVideoSendStream* stream2 = AddSendStream();
+  webrtc::FakeVideoSendStream* stream2 = AddSendStream();
   webrtc::VideoSendStream::Stats stats2;
   stats2.target_media_bitrate_bps = 200;
   stats2.media_bitrate_bps = 321;
@@ -7043,12 +7063,13 @@
 
   ASSERT_EQ(1u, fake_call_->GetVideoReceiveStreams().size())
       << "No default receive stream created.";
-  FakeVideoReceiveStream* recv_stream = fake_call_->GetVideoReceiveStreams()[0];
+  webrtc::FakeVideoReceiveStream* recv_stream =
+      fake_call_->GetVideoReceiveStreams()[0];
   EXPECT_EQ(0u, recv_stream->GetConfig().rtp.rtx_ssrc)
       << "Default receive stream should not have configured RTX";
 
   EXPECT_TRUE(receive_channel_->AddRecvStream(
-      cricket::CreateSimWithRtxStreamParams("cname", ssrcs, rtx_ssrcs)));
+      webrtc::CreateSimWithRtxStreamParams("cname", ssrcs, rtx_ssrcs)));
   ASSERT_EQ(1u, fake_call_->GetVideoReceiveStreams().size())
       << "AddRecvStream should have reconfigured, not added a new receiver.";
   recv_stream = fake_call_->GetVideoReceiveStreams()[0];
@@ -7069,7 +7090,7 @@
   const std::vector<uint32_t> rtx_ssrcs = MAKE_VECTOR(kRtxSsrcs1);
 
   StreamParams sp =
-      cricket::CreateSimWithRtxStreamParams("cname", ssrcs, rtx_ssrcs);
+      webrtc::CreateSimWithRtxStreamParams("cname", ssrcs, rtx_ssrcs);
   sp.ssrcs = ssrcs;  // Without RTXs, this is the important part.
 
   EXPECT_FALSE(send_channel_->AddSendStream(sp));
@@ -7083,7 +7104,7 @@
   const std::vector<uint32_t> rtx_ssrcs = MAKE_VECTOR(kRtxSsrcs1);
 
   StreamParams sp =
-      cricket::CreateSimWithRtxStreamParams("cname", ssrcs, rtx_ssrcs);
+      webrtc::CreateSimWithRtxStreamParams("cname", ssrcs, rtx_ssrcs);
 
   EXPECT_TRUE(send_channel_->AddSendStream(sp));
   EXPECT_TRUE(receive_channel_->AddRecvStream(sp));
@@ -7108,14 +7129,14 @@
   EXPECT_TRUE(send_channel_->SetSenderParameters(send_parameters_));
 
   StreamParams sp =
-      cricket::CreateSimStreamParams("cname", MAKE_VECTOR(kFirstStreamSsrcs));
+      webrtc::CreateSimStreamParams("cname", MAKE_VECTOR(kFirstStreamSsrcs));
 
   EXPECT_TRUE(send_channel_->AddSendStream(sp));
   EXPECT_TRUE(receive_channel_->AddRecvStream(sp));
 
   // One of the SSRCs is already used in previous streams, using it should fail.
-  sp = cricket::CreateSimStreamParams("cname",
-                                      MAKE_VECTOR(kOverlappingStreamSsrcs));
+  sp = webrtc::CreateSimStreamParams("cname",
+                                     MAKE_VECTOR(kOverlappingStreamSsrcs));
   EXPECT_FALSE(send_channel_->AddSendStream(sp));
   EXPECT_FALSE(receive_channel_->AddRecvStream(sp));
 
@@ -7133,7 +7154,7 @@
   static const uint32_t kSenderSsrcs[] = {4, 7, 10};
   static const uint32_t kSenderRtxSsrcs[] = {5, 8, 11};
 
-  StreamParams sender_sp = cricket::CreateSimWithRtxStreamParams(
+  StreamParams sender_sp = webrtc::CreateSimWithRtxStreamParams(
       "cname", MAKE_VECTOR(kSenderSsrcs), MAKE_VECTOR(kSenderRtxSsrcs));
 
   EXPECT_TRUE(send_channel_->AddSendStream(sender_sp));
@@ -7141,7 +7162,7 @@
   static const uint32_t kReceiverSsrcs[] = {3};
   static const uint32_t kReceiverRtxSsrcs[] = {2};
 
-  StreamParams receiver_sp = cricket::CreateSimWithRtxStreamParams(
+  StreamParams receiver_sp = webrtc::CreateSimWithRtxStreamParams(
       "cname", MAKE_VECTOR(kReceiverSsrcs), MAKE_VECTOR(kReceiverRtxSsrcs));
   EXPECT_TRUE(receive_channel_->AddRecvStream(receiver_sp));
 
@@ -7159,7 +7180,7 @@
 }
 
 TEST_F(WebRtcVideoChannelTest, MapsReceivedPayloadTypeToCodecName) {
-  FakeVideoReceiveStream* stream = AddRecvStream();
+  webrtc::FakeVideoReceiveStream* stream = AddRecvStream();
   webrtc::VideoReceiveStreamInterface::Stats stats;
 
   // Report no codec name before receiving.
@@ -7566,7 +7587,7 @@
 // Test BaseMinimumPlayoutDelayMs on unsignaled receive streams.
 TEST_F(WebRtcVideoChannelTest, BaseMinimumPlayoutDelayMsUnsignaledRecvStream) {
   std::optional<int> delay_ms;
-  const FakeVideoReceiveStream* recv_stream;
+  const webrtc::FakeVideoReceiveStream* recv_stream;
 
   // Set default stream with SSRC 0
   EXPECT_TRUE(receive_channel_->SetBaseMinimumPlayoutDelayMs(0, 200));
@@ -7752,7 +7773,7 @@
   EXPECT_TRUE(receive_channel_->SetReceiverParameters(parameters));
   // No receive streams yet.
   ASSERT_EQ(0u, fake_call_->GetVideoReceiveStreams().size());
-  cricket::FakeVideoRenderer renderer;
+  webrtc::FakeVideoRenderer renderer;
   receive_channel_->SetDefaultSink(&renderer);
 
   // Receive VP8 packet on first SSRC.
@@ -7762,7 +7783,8 @@
   ReceivePacketAndAdvanceTime(rtp_packet);
   // VP8 packet should create default receive stream.
   ASSERT_EQ(1u, fake_call_->GetVideoReceiveStreams().size());
-  FakeVideoReceiveStream* recv_stream = fake_call_->GetVideoReceiveStreams()[0];
+  webrtc::FakeVideoReceiveStream* recv_stream =
+      fake_call_->GetVideoReceiveStreams()[0];
   EXPECT_EQ(rtp_packet.Ssrc(), recv_stream->GetConfig().rtp.remote_ssrc);
   // Verify that the receive stream sinks to a renderer.
   webrtc::VideoFrame video_frame =
@@ -7836,7 +7858,7 @@
   ReceivePacketAndAdvanceTime(rtp_packet);
   // Default receive stream should be created.
   ASSERT_EQ(1u, fake_call_->GetVideoReceiveStreams().size());
-  FakeVideoReceiveStream* recv_stream0 =
+  webrtc::FakeVideoReceiveStream* recv_stream0 =
       fake_call_->GetVideoReceiveStreams()[0];
   EXPECT_EQ(kSsrcs3[0], recv_stream0->GetConfig().rtp.remote_ssrc);
 
@@ -7853,7 +7875,7 @@
   // New default receive stream should be created, but old stream should remain.
   ASSERT_EQ(2u, fake_call_->GetVideoReceiveStreams().size());
   EXPECT_EQ(recv_stream0, fake_call_->GetVideoReceiveStreams()[0]);
-  FakeVideoReceiveStream* recv_stream1 =
+  webrtc::FakeVideoReceiveStream* recv_stream1 =
       fake_call_->GetVideoReceiveStreams()[1];
   EXPECT_EQ(kSsrcs3[1], recv_stream1->GetConfig().rtp.remote_ssrc);
 }
@@ -7899,7 +7921,7 @@
 
 TEST_F(WebRtcVideoChannelTest,
        SetLowMaxBitrateOverwritesVideoStreamMinBitrate) {
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
 
   webrtc::RtpParameters parameters =
       send_channel_->GetRtpSendParameters(last_ssrc_);
@@ -7929,7 +7951,7 @@
 
 TEST_F(WebRtcVideoChannelTest,
        SetHighMinBitrateOverwritesVideoStreamMaxBitrate) {
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
 
   // Note that this is testing the behavior of the FakeVideoSendStream, which
   // also calls to CreateEncoderStreams to get the VideoStreams, so essentially
@@ -7953,7 +7975,7 @@
 TEST_F(WebRtcVideoChannelTest,
        SetMinBitrateAboveMaxBitrateLimitAdjustsMinBitrateDown) {
   send_parameters_.max_bandwidth_bps = 99999;
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
   ExpectSetMaxBitrate(send_parameters_.max_bandwidth_bps);
   ASSERT_TRUE(send_channel_->SetSenderParameters(send_parameters_));
   ASSERT_EQ(1UL, stream->GetVideoStreams().size());
@@ -7977,7 +7999,7 @@
 }
 
 TEST_F(WebRtcVideoChannelTest, SetMaxFramerateOneStream) {
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
 
   webrtc::RtpParameters parameters =
       send_channel_->GetRtpSendParameters(last_ssrc_);
@@ -8004,7 +8026,7 @@
 }
 
 TEST_F(WebRtcVideoChannelTest, SetNumTemporalLayersForSingleStream) {
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
 
   webrtc::RtpParameters parameters =
       send_channel_->GetRtpSendParameters(last_ssrc_);
@@ -8046,7 +8068,7 @@
 TEST_F(WebRtcVideoChannelTest,
        CannotSetSimulcastRtpSendParametersWithIncorrectNumberOfEncodings) {
   std::vector<uint32_t> ssrcs = MAKE_VECTOR(kSsrcs3);
-  StreamParams sp = CreateSimStreamParams("cname", ssrcs);
+  StreamParams sp = webrtc::CreateSimStreamParams("cname", ssrcs);
   AddSendStream(sp);
 
   webrtc::RtpParameters parameters =
@@ -8112,10 +8134,10 @@
   EXPECT_EQ(new_bitrate_priority, parameters.encodings[0].bitrate_priority);
 
   // Verify that the new value propagated down to the encoder.
-  std::vector<FakeVideoSendStream*> video_send_streams =
+  std::vector<webrtc::FakeVideoSendStream*> video_send_streams =
       fake_call_->GetVideoSendStreams();
   EXPECT_EQ(1UL, video_send_streams.size());
-  FakeVideoSendStream* video_send_stream = video_send_streams.front();
+  webrtc::FakeVideoSendStream* video_send_stream = video_send_streams.front();
   // Check that the WebRtcVideoSendStream updated the VideoEncoderConfig
   // appropriately.
   EXPECT_EQ(new_bitrate_priority,
@@ -8134,7 +8156,7 @@
   // Create the stream params with multiple ssrcs for simulcast.
   const size_t kNumSimulcastStreams = 3;
   std::vector<uint32_t> ssrcs = MAKE_VECTOR(kSsrcs3);
-  StreamParams stream_params = CreateSimStreamParams("cname", ssrcs);
+  StreamParams stream_params = webrtc::CreateSimStreamParams("cname", ssrcs);
   AddSendStream(stream_params);
   uint32_t primary_ssrc = stream_params.first_ssrc();
 
@@ -8168,10 +8190,10 @@
   EXPECT_EQ(new_bitrate_priority, parameters.encodings[0].bitrate_priority);
 
   // Verify that the new value propagated down to the encoder.
-  std::vector<FakeVideoSendStream*> video_send_streams =
+  std::vector<webrtc::FakeVideoSendStream*> video_send_streams =
       fake_call_->GetVideoSendStreams();
   EXPECT_EQ(1UL, video_send_streams.size());
-  FakeVideoSendStream* video_send_stream = video_send_streams.front();
+  webrtc::FakeVideoSendStream* video_send_stream = video_send_streams.front();
   // Check that the WebRtcVideoSendStream updated the VideoEncoderConfig
   // appropriately.
   EXPECT_EQ(kNumSimulcastStreams,
@@ -8219,7 +8241,8 @@
   codec.id = 123;
   parameters.codecs.push_back(codec);
   ASSERT_TRUE(send_channel_->SetSenderParameters(parameters));
-  FakeVideoSendStream* stream = SetUpSimulcast(true, /*with_rtx=*/false);
+  webrtc::FakeVideoSendStream* stream =
+      SetUpSimulcast(true, /*with_rtx=*/false);
   webrtc::test::FrameForwarder frame_forwarder;
   EXPECT_TRUE(send_channel_->SetVideoSend(last_ssrc_, /*options=*/nullptr,
                                           &frame_forwarder));
@@ -8240,9 +8263,9 @@
 
   // Use a capture resolution whose width and height are not divisible by 2^3.
   // (See field trial set at the top of the test.)
-  FakeFrameSource frame_source(test_params.resolution.width,
-                               test_params.resolution.height,
-                               rtc::kNumMicrosecsPerSec / 30);
+  webrtc::FakeFrameSource frame_source(test_params.resolution.width,
+                                       test_params.resolution.height,
+                                       rtc::kNumMicrosecsPerSec / 30);
   frame_forwarder.IncomingCapturedFrame(frame_source.GetFrame());
 
   // Ensure the scaling is correct.
@@ -8378,7 +8401,8 @@
 }
 
 TEST_F(WebRtcVideoChannelTest, NumTemporalLayersPropagatedToEncoder) {
-  FakeVideoSendStream* stream = SetUpSimulcast(true, /*with_rtx=*/false);
+  webrtc::FakeVideoSendStream* stream =
+      SetUpSimulcast(true, /*with_rtx=*/false);
 
   // Send a full size frame so all simulcast layers are used when reconfiguring.
   webrtc::test::FrameForwarder frame_forwarder;
@@ -8425,7 +8449,8 @@
 TEST_F(WebRtcVideoChannelTest,
        DefaultValuePropagatedToEncoderForUnsetNumTemporalLayers) {
   const size_t kDefaultNumTemporalLayers = 3;
-  FakeVideoSendStream* stream = SetUpSimulcast(true, /*with_rtx=*/false);
+  webrtc::FakeVideoSendStream* stream =
+      SetUpSimulcast(true, /*with_rtx=*/false);
 
   // Send a full size frame so all simulcast layers are used when reconfiguring.
   webrtc::test::FrameForwarder frame_forwarder;
@@ -8465,7 +8490,8 @@
 TEST_F(WebRtcVideoChannelTest,
        DefaultValuePropagatedToEncoderForUnsetFramerate) {
   const std::vector<webrtc::VideoStream> kDefault = GetSimulcastBitrates720p();
-  FakeVideoSendStream* stream = SetUpSimulcast(true, /*with_rtx=*/false);
+  webrtc::FakeVideoSendStream* stream =
+      SetUpSimulcast(true, /*with_rtx=*/false);
 
   // Send a full size frame so all simulcast layers are used when reconfiguring.
   webrtc::test::FrameForwarder frame_forwarder;
@@ -8513,7 +8539,8 @@
   encoder_factory_->AddSupportedVideoCodec(webrtc::SdpVideoFormat(
       "VP8", webrtc::CodecParameterMap(), kSupportedModes));
 
-  FakeVideoSendStream* stream = SetUpSimulcast(true, /*with_rtx=*/false);
+  webrtc::FakeVideoSendStream* stream =
+      SetUpSimulcast(true, /*with_rtx=*/false);
 
   // Send a full size frame so all simulcast layers are used when reconfiguring.
   webrtc::test::FrameForwarder frame_forwarder;
@@ -8588,7 +8615,8 @@
   send_parameters.codecs.push_back(GetEngineCodec("H265"));
   EXPECT_TRUE(send_channel_->SetSenderParameters(send_parameters));
 
-  FakeVideoSendStream* stream = SetUpSimulcast(true, /*with_rtx=*/false);
+  webrtc::FakeVideoSendStream* stream =
+      SetUpSimulcast(true, /*with_rtx=*/false);
 
   // Send a full size frame so all simulcast layers are used when reconfiguring.
   webrtc::test::FrameForwarder frame_forwarder;
@@ -8668,7 +8696,7 @@
   }
 
   EXPECT_TRUE(send_channel_->SetSenderParameters(send_parameters));
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
   ASSERT_TRUE(stream);
 
   webrtc::test::FrameForwarder frame_forwarder;
@@ -8689,7 +8717,8 @@
     }
   }
 
-  FakeVideoSendStream* send_stream = fake_call_->GetVideoSendStreams().front();
+  webrtc::FakeVideoSendStream* send_stream =
+      fake_call_->GetVideoSendStreams().front();
   ASSERT_TRUE(send_stream);
   webrtc::VideoEncoderConfig encoder_config =
       send_stream->GetEncoderConfig().Copy();
@@ -8710,7 +8739,8 @@
     }
   }
 
-  FakeVideoSendStream* send_stream2 = fake_call_->GetVideoSendStreams().front();
+  webrtc::FakeVideoSendStream* send_stream2 =
+      fake_call_->GetVideoSendStreams().front();
   ASSERT_TRUE(send_stream2);
   webrtc::VideoEncoderConfig encoder_config2 =
       send_stream2->GetEncoderConfig().Copy();
@@ -8737,7 +8767,7 @@
   }
 
   EXPECT_TRUE(send_channel_->SetSenderParameters(send_parameters));
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
   ASSERT_TRUE(stream);
 
   webrtc::test::FrameForwarder frame_forwarder;
@@ -8758,7 +8788,8 @@
     }
   }
 
-  FakeVideoSendStream* send_stream = fake_call_->GetVideoSendStreams().front();
+  webrtc::FakeVideoSendStream* send_stream =
+      fake_call_->GetVideoSendStreams().front();
   ASSERT_TRUE(send_stream);
   webrtc::VideoEncoderConfig encoder_config =
       send_stream->GetEncoderConfig().Copy();
@@ -8781,7 +8812,8 @@
     }
   }
 
-  FakeVideoSendStream* send_stream2 = fake_call_->GetVideoSendStreams().front();
+  webrtc::FakeVideoSendStream* send_stream2 =
+      fake_call_->GetVideoSendStreams().front();
   ASSERT_TRUE(send_stream2);
   webrtc::VideoEncoderConfig encoder_config2 =
       send_stream2->GetEncoderConfig().Copy();
@@ -8808,7 +8840,7 @@
   }
 
   EXPECT_TRUE(send_channel_->SetSenderParameters(send_parameters));
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
   ASSERT_TRUE(stream);
 
   webrtc::test::FrameForwarder frame_forwarder;
@@ -8829,7 +8861,8 @@
     }
   }
 
-  FakeVideoSendStream* send_stream = fake_call_->GetVideoSendStreams().front();
+  webrtc::FakeVideoSendStream* send_stream =
+      fake_call_->GetVideoSendStreams().front();
   ASSERT_TRUE(send_stream);
   webrtc::VideoEncoderConfig encoder_config =
       send_stream->GetEncoderConfig().Copy();
@@ -8850,7 +8883,8 @@
       EXPECT_EQ(codec.parameters.at("level-id"), "156");
     }
   }
-  FakeVideoSendStream* send_stream2 = fake_call_->GetVideoSendStreams().front();
+  webrtc::FakeVideoSendStream* send_stream2 =
+      fake_call_->GetVideoSendStreams().front();
   ASSERT_TRUE(send_stream2);
   webrtc::VideoEncoderConfig encoder_config2 =
       send_stream2->GetEncoderConfig().Copy();
@@ -8873,7 +8907,8 @@
   send_parameters.codecs.push_back(GetEngineCodec("VP9"));
   EXPECT_TRUE(send_channel_->SetSenderParameters(send_parameters));
 
-  FakeVideoSendStream* stream = SetUpSimulcast(true, /*with_rtx=*/false);
+  webrtc::FakeVideoSendStream* stream =
+      SetUpSimulcast(true, /*with_rtx=*/false);
 
   // Send a full size frame so all simulcast layers are used when reconfiguring.
   webrtc::test::FrameForwarder frame_forwarder;
@@ -8929,7 +8964,7 @@
   frame_forwarder.IncomingCapturedFrame(frame_source_.GetFrame());
 
   // The stream should be recreated due to codec change.
-  std::vector<FakeVideoSendStream*> new_streams = GetFakeSendStreams();
+  std::vector<webrtc::FakeVideoSendStream*> new_streams = GetFakeSendStreams();
   EXPECT_EQ(1u, new_streams.size());
   EXPECT_EQ(2, fake_call_->GetNumCreatedSendStreams());
 
@@ -9007,7 +9042,8 @@
 // the maximum (3/4 was chosen because it's similar to the simulcast defaults
 // that are used if no min/max are specified).
 TEST_F(WebRtcVideoChannelTest, MinAndMaxSimulcastBitratePropagatedToEncoder) {
-  FakeVideoSendStream* stream = SetUpSimulcast(true, /*with_rtx=*/false);
+  webrtc::FakeVideoSendStream* stream =
+      SetUpSimulcast(true, /*with_rtx=*/false);
 
   // Send a full size frame so all simulcast layers are used when reconfiguring.
   webrtc::test::FrameForwarder frame_forwarder;
@@ -9071,7 +9107,8 @@
 // simulcast default that is used if no min/max are specified.
 TEST_F(WebRtcVideoChannelTest, MinOrMaxSimulcastBitratePropagatedToEncoder) {
   const std::vector<webrtc::VideoStream> kDefault = GetSimulcastBitrates720p();
-  FakeVideoSendStream* stream = SetUpSimulcast(true, /*with_rtx=*/false);
+  webrtc::FakeVideoSendStream* stream =
+      SetUpSimulcast(true, /*with_rtx=*/false);
 
   // Send a full size frame so all simulcast layers are used when reconfiguring.
   webrtc::test::FrameForwarder frame_forwarder;
@@ -9141,7 +9178,8 @@
 // unspecified values accordingly.
 TEST_F(WebRtcVideoChannelTest, SetMinAndMaxSimulcastBitrateAboveBelowDefault) {
   const std::vector<webrtc::VideoStream> kDefault = GetSimulcastBitrates720p();
-  FakeVideoSendStream* stream = SetUpSimulcast(true, /*with_rtx=*/false);
+  webrtc::FakeVideoSendStream* stream =
+      SetUpSimulcast(true, /*with_rtx=*/false);
 
   // Send a full size frame so all simulcast layers are used when reconfiguring.
   webrtc::test::FrameForwarder frame_forwarder;
@@ -9190,7 +9228,8 @@
 
 TEST_F(WebRtcVideoChannelTest, BandwidthAboveTotalMaxBitrateGivenToMaxLayer) {
   const std::vector<webrtc::VideoStream> kDefault = GetSimulcastBitrates720p();
-  FakeVideoSendStream* stream = SetUpSimulcast(true, /*with_rtx=*/false);
+  webrtc::FakeVideoSendStream* stream =
+      SetUpSimulcast(true, /*with_rtx=*/false);
 
   // Send a full size frame so all simulcast layers are used when reconfiguring.
   webrtc::test::FrameForwarder frame_forwarder;
@@ -9240,7 +9279,8 @@
        BandwidthAboveTotalMaxBitrateNotGivenToMaxLayerIfMaxBitrateSet) {
   const std::vector<webrtc::VideoStream> kDefault = GetSimulcastBitrates720p();
   EXPECT_EQ(kNumSimulcastStreams, kDefault.size());
-  FakeVideoSendStream* stream = SetUpSimulcast(true, /*with_rtx=*/false);
+  webrtc::FakeVideoSendStream* stream =
+      SetUpSimulcast(true, /*with_rtx=*/false);
 
   // Send a full size frame so all simulcast layers are used when reconfiguring.
   webrtc::test::FrameForwarder frame_forwarder;
@@ -9276,7 +9316,7 @@
   webrtc::test::ScopedKeyValueConfig field_trials(
       field_trials_, "WebRTC-MixedCodecSimulcast/Enabled/");
 
-  StreamParams sp = CreateSimStreamParams("cname", {123, 456, 789});
+  StreamParams sp = webrtc::CreateSimStreamParams("cname", {123, 456, 789});
 
   std::vector<cricket::RidDescription> rid_descriptions;
   rid_descriptions.emplace_back("f", cricket::RidDirection::kSend);
@@ -9350,7 +9390,7 @@
 // Test that min and max bitrate values set via RtpParameters are correctly
 // propagated to the underlying encoder for a single stream.
 TEST_F(WebRtcVideoChannelTest, MinAndMaxBitratePropagatedToEncoder) {
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
   EXPECT_TRUE(send_channel_->SetSend(true));
   EXPECT_TRUE(stream->IsSending());
 
@@ -9381,7 +9421,7 @@
 // underlying encoder for a single stream (when the values are not set via
 // RtpParameters).
 TEST_F(WebRtcVideoChannelTest, DefaultMinAndMaxBitratePropagatedToEncoder) {
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
   EXPECT_TRUE(send_channel_->SetSend(true));
   EXPECT_TRUE(stream->IsSending());
 
@@ -9410,8 +9450,9 @@
   // Create the stream params with multiple ssrcs for simulcast.
   const size_t kNumSimulcastStreams = 3;
   std::vector<uint32_t> ssrcs = MAKE_VECTOR(kSsrcs3);
-  StreamParams stream_params = CreateSimStreamParams("cname", ssrcs);
-  FakeVideoSendStream* fake_video_send_stream = AddSendStream(stream_params);
+  StreamParams stream_params = webrtc::CreateSimStreamParams("cname", ssrcs);
+  webrtc::FakeVideoSendStream* fake_video_send_stream =
+      AddSendStream(stream_params);
   uint32_t primary_ssrc = stream_params.first_ssrc();
 
   // Using the FrameForwarder, we manually send a full size
@@ -9586,7 +9627,7 @@
   parameters.codecs.push_back(kH264sprop2);
   EXPECT_TRUE(receive_channel_->SetReceiverParameters(parameters));
 
-  FakeVideoReceiveStream* recv_stream = AddRecvStream();
+  webrtc::FakeVideoReceiveStream* recv_stream = AddRecvStream();
   const webrtc::VideoReceiveStreamInterface::Config& cfg =
       recv_stream->GetConfig();
   webrtc::RtpParameters rtp_parameters =
@@ -9656,7 +9697,7 @@
             receive_channel_->GetDefaultRtpReceiveParameters());
 
   // Set a sink for an unsignaled stream.
-  cricket::FakeVideoRenderer renderer;
+  webrtc::FakeVideoRenderer renderer;
   receive_channel_->SetDefaultSink(&renderer);
 
   // Call GetDefaultRtpReceiveParameters before the SSRC is known.
@@ -9706,7 +9747,7 @@
 
   if (receiver_first) {
     AddRecvStream(StreamParams::CreateLegacy(kReceiverSsrc));
-    std::vector<FakeVideoReceiveStream*> receive_streams =
+    std::vector<webrtc::FakeVideoReceiveStream*> receive_streams =
         fake_call_->GetVideoReceiveStreams();
     ASSERT_EQ(1u, receive_streams.size());
     // Default local SSRC when we have no sender.
@@ -9716,7 +9757,7 @@
   AddSendStream(StreamParams::CreateLegacy(kSenderSsrc));
   if (!receiver_first)
     AddRecvStream(StreamParams::CreateLegacy(kReceiverSsrc));
-  std::vector<FakeVideoReceiveStream*> receive_streams =
+  std::vector<webrtc::FakeVideoReceiveStream*> receive_streams =
       fake_call_->GetVideoReceiveStreams();
   ASSERT_EQ(1u, receive_streams.size());
   EXPECT_EQ(kSenderSsrc, receive_streams[0]->GetConfig().rtp.local_ssrc);
@@ -9746,12 +9787,13 @@
 }
 
 TEST_F(WebRtcVideoChannelTest, Simulcast_QualityScalingNotAllowed) {
-  FakeVideoSendStream* stream = SetUpSimulcast(true, /*with_rtx=*/true);
+  webrtc::FakeVideoSendStream* stream = SetUpSimulcast(true, /*with_rtx=*/true);
   EXPECT_FALSE(stream->GetEncoderConfig().is_quality_scaling_allowed);
 }
 
 TEST_F(WebRtcVideoChannelTest, Singlecast_QualityScalingAllowed) {
-  FakeVideoSendStream* stream = SetUpSimulcast(false, /*with_rtx=*/true);
+  webrtc::FakeVideoSendStream* stream =
+      SetUpSimulcast(false, /*with_rtx=*/true);
   EXPECT_TRUE(stream->GetEncoderConfig().is_quality_scaling_allowed);
 }
 
@@ -9766,7 +9808,8 @@
       send_channel_->SetVideoSend(last_ssrc_, &options, &frame_forwarder));
   // Fetch the latest stream since SetVideoSend() may recreate it if the
   // screen content setting is changed.
-  FakeVideoSendStream* stream = fake_call_->GetVideoSendStreams().front();
+  webrtc::FakeVideoSendStream* stream =
+      fake_call_->GetVideoSendStreams().front();
 
   EXPECT_FALSE(stream->GetEncoderConfig().is_quality_scaling_allowed);
   EXPECT_TRUE(send_channel_->SetVideoSend(last_ssrc_, nullptr, nullptr));
@@ -9774,7 +9817,8 @@
 
 TEST_F(WebRtcVideoChannelTest,
        SimulcastSingleActiveStream_QualityScalingAllowed) {
-  FakeVideoSendStream* stream = SetUpSimulcast(true, /*with_rtx=*/false);
+  webrtc::FakeVideoSendStream* stream =
+      SetUpSimulcast(true, /*with_rtx=*/false);
 
   webrtc::RtpParameters rtp_parameters =
       send_channel_->GetRtpSendParameters(last_ssrc_);
@@ -9790,7 +9834,7 @@
 }
 
 TEST_F(WebRtcVideoChannelTest, GenerateKeyFrameSinglecast) {
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
 
   webrtc::RtpParameters rtp_parameters =
       send_channel_->GetRtpSendParameters(last_ssrc_);
@@ -9811,7 +9855,8 @@
 }
 
 TEST_F(WebRtcVideoChannelTest, GenerateKeyFrameSimulcast) {
-  StreamParams stream_params = CreateSimStreamParams("cname", {123, 456, 789});
+  StreamParams stream_params =
+      webrtc::CreateSimStreamParams("cname", {123, 456, 789});
 
   std::vector<std::string> rids = {"f", "h", "q"};
   std::vector<cricket::RidDescription> rid_descriptions;
@@ -9819,7 +9864,7 @@
     rid_descriptions.emplace_back(rid, cricket::RidDirection::kSend);
   }
   stream_params.set_rids(rid_descriptions);
-  FakeVideoSendStream* stream = AddSendStream(stream_params);
+  webrtc::FakeVideoSendStream* stream = AddSendStream(stream_params);
 
   webrtc::RtpParameters rtp_parameters =
       send_channel_->GetRtpSendParameters(last_ssrc_);
@@ -9871,13 +9916,13 @@
  public:
   WebRtcVideoChannelSimulcastTest()
       : fake_call_(CreateEnvironment(&field_trials_)),
-        encoder_factory_(new cricket::FakeWebRtcVideoEncoderFactory),
-        decoder_factory_(new cricket::FakeWebRtcVideoDecoderFactory),
+        encoder_factory_(new webrtc::FakeWebRtcVideoEncoderFactory),
+        decoder_factory_(new webrtc::FakeWebRtcVideoDecoderFactory),
         mock_rate_allocator_factory_(
             std::make_unique<webrtc::MockVideoBitrateAllocatorFactory>()),
-        engine_(std::unique_ptr<cricket::FakeWebRtcVideoEncoderFactory>(
+        engine_(std::unique_ptr<webrtc::FakeWebRtcVideoEncoderFactory>(
                     encoder_factory_),
-                std::unique_ptr<cricket::FakeWebRtcVideoDecoderFactory>(
+                std::unique_ptr<webrtc::FakeWebRtcVideoDecoderFactory>(
                     decoder_factory_),
                 field_trials_),
         last_ssrc_(0) {}
@@ -9915,12 +9960,12 @@
     RTC_DCHECK(num_configured_streams <= ssrcs.size());
     ssrcs.resize(num_configured_streams);
 
-    AddSendStream(CreateSimStreamParams("cname", ssrcs));
+    AddSendStream(webrtc::CreateSimStreamParams("cname", ssrcs));
     // Send a full-size frame to trigger a stream reconfiguration to use all
     // expected simulcast layers.
     webrtc::test::FrameForwarder frame_forwarder;
-    cricket::FakeFrameSource frame_source(capture_width, capture_height,
-                                          rtc::kNumMicrosecsPerSec / 30);
+    webrtc::FakeFrameSource frame_source(capture_width, capture_height,
+                                         rtc::kNumMicrosecsPerSec / 30);
 
     VideoOptions options;
     if (screenshare)
@@ -9929,7 +9974,8 @@
         send_channel_->SetVideoSend(ssrcs.front(), &options, &frame_forwarder));
     // Fetch the latest stream since SetVideoSend() may recreate it if the
     // screen content setting is changed.
-    FakeVideoSendStream* stream = fake_call_.GetVideoSendStreams().front();
+    webrtc::FakeVideoSendStream* stream =
+        fake_call_.GetVideoSendStreams().front();
     send_channel_->SetSend(true);
     frame_forwarder.IncomingCapturedFrame(frame_source.GetFrame());
 
@@ -10006,40 +10052,40 @@
     EXPECT_TRUE(send_channel_->SetVideoSend(ssrcs.front(), nullptr, nullptr));
   }
 
-  FakeVideoSendStream* AddSendStream() {
+  webrtc::FakeVideoSendStream* AddSendStream() {
     return AddSendStream(StreamParams::CreateLegacy(last_ssrc_++));
   }
 
-  FakeVideoSendStream* AddSendStream(const StreamParams& sp) {
+  webrtc::FakeVideoSendStream* AddSendStream(const StreamParams& sp) {
     size_t num_streams = fake_call_.GetVideoSendStreams().size();
     EXPECT_TRUE(send_channel_->AddSendStream(sp));
-    std::vector<FakeVideoSendStream*> streams =
+    std::vector<webrtc::FakeVideoSendStream*> streams =
         fake_call_.GetVideoSendStreams();
     EXPECT_EQ(num_streams + 1, streams.size());
     return streams[streams.size() - 1];
   }
 
-  std::vector<FakeVideoSendStream*> GetFakeSendStreams() {
+  std::vector<webrtc::FakeVideoSendStream*> GetFakeSendStreams() {
     return fake_call_.GetVideoSendStreams();
   }
 
-  FakeVideoReceiveStream* AddRecvStream() {
+  webrtc::FakeVideoReceiveStream* AddRecvStream() {
     return AddRecvStream(StreamParams::CreateLegacy(last_ssrc_++));
   }
 
-  FakeVideoReceiveStream* AddRecvStream(const StreamParams& sp) {
+  webrtc::FakeVideoReceiveStream* AddRecvStream(const StreamParams& sp) {
     size_t num_streams = fake_call_.GetVideoReceiveStreams().size();
     EXPECT_TRUE(receive_channel_->AddRecvStream(sp));
-    std::vector<FakeVideoReceiveStream*> streams =
+    std::vector<webrtc::FakeVideoReceiveStream*> streams =
         fake_call_.GetVideoReceiveStreams();
     EXPECT_EQ(num_streams + 1, streams.size());
     return streams[streams.size() - 1];
   }
 
   webrtc::test::ScopedKeyValueConfig field_trials_;
-  FakeCall fake_call_;
-  cricket::FakeWebRtcVideoEncoderFactory* encoder_factory_;
-  cricket::FakeWebRtcVideoDecoderFactory* decoder_factory_;
+  webrtc::FakeCall fake_call_;
+  webrtc::FakeWebRtcVideoEncoderFactory* encoder_factory_;
+  webrtc::FakeWebRtcVideoDecoderFactory* decoder_factory_;
   std::unique_ptr<webrtc::MockVideoBitrateAllocatorFactory>
       mock_rate_allocator_factory_;
   WebRtcVideoEngine engine_;
@@ -10120,7 +10166,7 @@
 }
 
 TEST_F(WebRtcVideoChannelTest, SetsRidsOnSendStream) {
-  StreamParams sp = CreateSimStreamParams("cname", {123, 456, 789});
+  StreamParams sp = webrtc::CreateSimStreamParams("cname", {123, 456, 789});
 
   std::vector<std::string> rids = {"f", "h", "q"};
   std::vector<cricket::RidDescription> rid_descriptions;
@@ -10171,10 +10217,10 @@
   parameters.codecs.push_back(GetEngineCodec("VP8"));
   ASSERT_TRUE(send_channel_->SetSenderParameters(parameters));
 
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
   webrtc::test::FrameForwarder frame_forwarder;
-  cricket::FakeFrameSource frame_source(1280, 720,
-                                        rtc::kNumMicrosecsPerSec / 30);
+  webrtc::FakeFrameSource frame_source(1280, 720,
+                                       rtc::kNumMicrosecsPerSec / 30);
   EXPECT_TRUE(
       send_channel_->SetVideoSend(last_ssrc_, nullptr, &frame_forwarder));
 
@@ -10230,10 +10276,10 @@
   parameters.codecs.push_back(GetEngineCodec("VP8"));
   ASSERT_TRUE(send_channel_->SetSenderParameters(parameters));
 
-  FakeVideoSendStream* stream = AddSendStream();
+  webrtc::FakeVideoSendStream* stream = AddSendStream();
   webrtc::test::FrameForwarder frame_forwarder;
-  cricket::FakeFrameSource frame_source(1280, 720,
-                                        rtc::kNumMicrosecsPerSec / 30);
+  webrtc::FakeFrameSource frame_source(1280, 720,
+                                       rtc::kNumMicrosecsPerSec / 30);
   EXPECT_TRUE(
       send_channel_->SetVideoSend(last_ssrc_, nullptr, &frame_forwarder));
 
@@ -10307,10 +10353,11 @@
   parameters.codecs.push_back(GetEngineCodec("VP8"));
   ASSERT_TRUE(send_channel_->SetSenderParameters(parameters));
 
-  FakeVideoSendStream* stream = SetUpSimulcast(true, /*with_rtx=*/false);
+  webrtc::FakeVideoSendStream* stream =
+      SetUpSimulcast(true, /*with_rtx=*/false);
   webrtc::test::FrameForwarder frame_forwarder;
-  cricket::FakeFrameSource frame_source(1280, 720,
-                                        rtc::kNumMicrosecsPerSec / 30);
+  webrtc::FakeFrameSource frame_source(1280, 720,
+                                       rtc::kNumMicrosecsPerSec / 30);
   EXPECT_TRUE(
       send_channel_->SetVideoSend(last_ssrc_, nullptr, &frame_forwarder));
 
diff --git a/media/engine/webrtc_voice_engine_unittest.cc b/media/engine/webrtc_voice_engine_unittest.cc
index cb903f1..a529a3d 100644
--- a/media/engine/webrtc_voice_engine_unittest.cc
+++ b/media/engine/webrtc_voice_engine_unittest.cc
@@ -357,13 +357,13 @@
     rtc::Thread::Current()->ProcessMessages(0);
   }
 
-  const cricket::FakeAudioSendStream& GetSendStream(uint32_t ssrc) {
+  const webrtc::FakeAudioSendStream& GetSendStream(uint32_t ssrc) {
     const auto* send_stream = call_.GetAudioSendStream(ssrc);
     EXPECT_TRUE(send_stream);
     return *send_stream;
   }
 
-  const cricket::FakeAudioReceiveStream& GetRecvStream(uint32_t ssrc) {
+  const webrtc::FakeAudioReceiveStream& GetRecvStream(uint32_t ssrc) {
     const auto* recv_stream = call_.GetAudioReceiveStream(ssrc);
     EXPECT_TRUE(recv_stream);
     return *recv_stream;
@@ -448,7 +448,7 @@
     EXPECT_FALSE(send_channel_->InsertDtmf(-1, 1, 111));
 
     // Test send.
-    cricket::FakeAudioSendStream::TelephoneEvent telephone_event =
+    webrtc::FakeAudioSendStream::TelephoneEvent telephone_event =
         GetSendStream(kSsrcX).GetLatestTelephoneEvent();
     EXPECT_EQ(-1, telephone_event.payload_type);
     EXPECT_TRUE(send_channel_->InsertDtmf(ssrc, 2, 123));
@@ -918,7 +918,7 @@
   const Environment env_;
   rtc::scoped_refptr<webrtc::test::MockAudioDeviceModule> adm_;
   rtc::scoped_refptr<StrictMock<webrtc::test::MockAudioProcessing>> apm_;
-  cricket::FakeCall call_;
+  webrtc::FakeCall call_;
   FakeAudioSource fake_source_;
   std::unique_ptr<cricket::WebRtcVoiceEngine> engine_;
   std::unique_ptr<cricket::VoiceMediaSendChannelInterface> send_channel_;
@@ -2820,9 +2820,9 @@
     webrtc::SetBE32(packets[i] + 8, static_cast<uint32_t>(i));
   }
 
-  const cricket::FakeAudioReceiveStream& s1 = GetRecvStream(ssrc1);
-  const cricket::FakeAudioReceiveStream& s2 = GetRecvStream(ssrc2);
-  const cricket::FakeAudioReceiveStream& s3 = GetRecvStream(ssrc3);
+  const webrtc::FakeAudioReceiveStream& s1 = GetRecvStream(ssrc1);
+  const webrtc::FakeAudioReceiveStream& s2 = GetRecvStream(ssrc2);
+  const webrtc::FakeAudioReceiveStream& s3 = GetRecvStream(ssrc3);
 
   EXPECT_EQ(s1.received_packets(), 0);
   EXPECT_EQ(s2.received_packets(), 0);
@@ -3394,7 +3394,7 @@
 // This test verifies DSCP settings are properly applied on voice media channel.
 TEST_P(WebRtcVoiceEngineTestFake, TestSetDscpOptions) {
   EXPECT_TRUE(SetupSendStream());
-  cricket::FakeNetworkInterface network_interface;
+  webrtc::FakeNetworkInterface network_interface;
   cricket::MediaConfig config;
   std::unique_ptr<cricket::VoiceMediaSendChannelInterface> channel;
   webrtc::RtpParameters parameters;
@@ -3650,7 +3650,7 @@
       cricket::StreamParams::CreateLegacy(kAudioSsrc)));
 
   EXPECT_EQ(1u, call_.GetAudioReceiveStreams().size());
-  const cricket::FakeAudioReceiveStream* s =
+  const webrtc::FakeAudioReceiveStream* s =
       call_.GetAudioReceiveStream(kAudioSsrc);
   EXPECT_EQ(0, s->received_packets());
   webrtc::RtpPacketReceived parsed_packet;
diff --git a/media/sctp/dcsctp_transport_unittest.cc b/media/sctp/dcsctp_transport_unittest.cc
index a609e0f..ab17e51 100644
--- a/media/sctp/dcsctp_transport_unittest.cc
+++ b/media/sctp/dcsctp_transport_unittest.cc
@@ -89,7 +89,7 @@
     sctp_transport_->SetOnConnectedCallback([this]() { sink_.OnConnected(); });
   }
 
-  cricket::FakeDtlsTransport fake_dtls_transport_;
+  FakeDtlsTransport fake_dtls_transport_;
   webrtc::SimulatedClock simulated_clock_;
   Environment env_;
   dcsctp::MockDcSctpSocket* socket_;
diff --git a/modules/audio_coding/audio_network_adaptor/audio_network_adaptor_impl_unittest.cc b/modules/audio_coding/audio_network_adaptor/audio_network_adaptor_impl_unittest.cc
index 60b4db1..59c5eb8 100644
--- a/modules/audio_coding/audio_network_adaptor/audio_network_adaptor_impl_unittest.cc
+++ b/modules/audio_coding/audio_network_adaptor/audio_network_adaptor_impl_unittest.cc
@@ -176,7 +176,7 @@
      DumpEncoderRuntimeConfigIsCalledOnGetEncoderRuntimeConfig) {
   test::ScopedFieldTrials override_field_trials(
       "WebRTC-Audio-FecAdaptation/Enabled/");
-  rtc::ScopedFakeClock fake_clock;
+  ScopedFakeClock fake_clock;
   fake_clock.AdvanceTime(TimeDelta::Millis(kClockInitialTimeMs));
   auto states = CreateAudioNetworkAdaptor();
   AudioEncoderRuntimeConfig config;
@@ -194,7 +194,7 @@
 
 TEST(AudioNetworkAdaptorImplTest,
      DumpNetworkMetricsIsCalledOnSetNetworkMetrics) {
-  rtc::ScopedFakeClock fake_clock;
+  ScopedFakeClock fake_clock;
   fake_clock.AdvanceTime(TimeDelta::Millis(kClockInitialTimeMs));
 
   auto states = CreateAudioNetworkAdaptor();
diff --git a/modules/audio_coding/audio_network_adaptor/controller_manager_unittest.cc b/modules/audio_coding/audio_network_adaptor/controller_manager_unittest.cc
index dfc3d6f..866a04c 100644
--- a/modules/audio_coding/audio_network_adaptor/controller_manager_unittest.cc
+++ b/modules/audio_coding/audio_network_adaptor/controller_manager_unittest.cc
@@ -140,7 +140,7 @@
 }
 
 TEST(ControllerManagerTest, DoNotReorderBeforeMinReordingTime) {
-  rtc::ScopedFakeClock fake_clock;
+  ScopedFakeClock fake_clock;
   auto states = CreateControllerManager();
   CheckControllersOrder(&states, kChracteristicBandwithBps[0],
                         kChracteristicPacketLossFraction[0],
@@ -155,7 +155,7 @@
 }
 
 TEST(ControllerManagerTest, ReorderBeyondMinReordingTimeAndMinDistance) {
-  rtc::ScopedFakeClock fake_clock;
+  ScopedFakeClock fake_clock;
   auto states = CreateControllerManager();
   constexpr int kBandwidthBps =
       (kChracteristicBandwithBps[0] + kChracteristicBandwithBps[1]) / 2;
@@ -174,7 +174,7 @@
 }
 
 TEST(ControllerManagerTest, DoNotReorderIfNetworkMetricsChangeTooSmall) {
-  rtc::ScopedFakeClock fake_clock;
+  ScopedFakeClock fake_clock;
   auto states = CreateControllerManager();
   constexpr int kBandwidthBps =
       (kChracteristicBandwithBps[0] + kChracteristicBandwithBps[1]) / 2;
@@ -354,7 +354,7 @@
   const std::vector<int> encoder_frame_lengths_ms = {20, 60};
 
   constexpr int64_t kClockInitialTimeMs = 12345678;
-  rtc::ScopedFakeClock fake_clock;
+  ScopedFakeClock fake_clock;
   fake_clock.AdvanceTime(TimeDelta::Millis(kClockInitialTimeMs));
   auto debug_dump_writer =
       std::unique_ptr<MockDebugDumpWriter>(new NiceMock<MockDebugDumpWriter>());
@@ -417,7 +417,7 @@
 }
 
 TEST(ControllerManagerTest, CreateFromConfigStringAndCheckReordering) {
-  rtc::ScopedFakeClock fake_clock;
+  ScopedFakeClock fake_clock;
   audio_network_adaptor::config::ControllerManager config;
   config.set_min_reordering_time_ms(kMinReorderingTimeMs);
   config.set_min_reordering_squared_distance(kMinReorderingSquareDistance);
diff --git a/modules/audio_coding/codecs/opus/audio_encoder_opus_unittest.cc b/modules/audio_coding/codecs/opus/audio_encoder_opus_unittest.cc
index 12ff7b5..a7a5057 100644
--- a/modules/audio_coding/codecs/opus/audio_encoder_opus_unittest.cc
+++ b/modules/audio_coding/codecs/opus/audio_encoder_opus_unittest.cc
@@ -49,7 +49,7 @@
   MockAudioNetworkAdaptor* mock_audio_network_adaptor;
   MockSmoothingFilter* mock_bitrate_smoother;
   std::unique_ptr<AudioEncoderOpusImpl> encoder;
-  std::unique_ptr<rtc::ScopedFakeClock> fake_clock;
+  std::unique_ptr<ScopedFakeClock> fake_clock;
   AudioEncoderOpusConfig config;
 };
 
@@ -60,7 +60,7 @@
   std::unique_ptr<AudioEncoderOpusStates> states =
       std::make_unique<AudioEncoderOpusStates>();
   states->mock_audio_network_adaptor = nullptr;
-  states->fake_clock.reset(new rtc::ScopedFakeClock());
+  states->fake_clock.reset(new ScopedFakeClock());
   states->fake_clock->SetTime(Timestamp::Micros(kInitialTimeUs));
 
   MockAudioNetworkAdaptor** mock_ptr = &states->mock_audio_network_adaptor;
diff --git a/modules/audio_processing/audio_processing_unittest.cc b/modules/audio_processing/audio_processing_unittest.cc
index 38bd180..751f634 100644
--- a/modules/audio_processing/audio_processing_unittest.cc
+++ b/modules/audio_processing/audio_processing_unittest.cc
@@ -1500,7 +1500,7 @@
 }
 
 void ApmTest::VerifyDebugDumpTest(Format format) {
-  rtc::ScopedFakeClock fake_clock;
+  ScopedFakeClock fake_clock;
   const std::string in_filename = test::ResourcePath("ref03", "aecdump");
   std::string format_string;
   switch (format) {
diff --git a/modules/pacing/packet_router_unittest.cc b/modules/pacing/packet_router_unittest.cc
index 33ba74f..7b9467e 100644
--- a/modules/pacing/packet_router_unittest.cc
+++ b/modules/pacing/packet_router_unittest.cc
@@ -673,7 +673,7 @@
 }
 
 TEST(PacketRouterRembTest, ChangeSendRtpModuleChangeRembSender) {
-  rtc::ScopedFakeClock clock;
+  ScopedFakeClock clock;
   NiceMock<MockRtpRtcpInterface> rtp_send;
   NiceMock<MockRtpRtcpInterface> rtp_recv;
   PacketRouter packet_router;
@@ -698,7 +698,7 @@
 // Only register receiving modules and make sure we fallback to trigger a REMB
 // packet on this one.
 TEST(PacketRouterRembTest, NoSendingRtpModule) {
-  rtc::ScopedFakeClock clock;
+  ScopedFakeClock clock;
   NiceMock<MockRtpRtcpInterface> rtp;
   PacketRouter packet_router;
 
@@ -719,7 +719,7 @@
 }
 
 TEST(PacketRouterRembTest, NonCandidateSendRtpModuleNotUsedForRemb) {
-  rtc::ScopedFakeClock clock;
+  ScopedFakeClock clock;
   PacketRouter packet_router;
   NiceMock<MockRtpRtcpInterface> module;
 
@@ -737,7 +737,7 @@
 }
 
 TEST(PacketRouterRembTest, CandidateSendRtpModuleUsedForRemb) {
-  rtc::ScopedFakeClock clock;
+  ScopedFakeClock clock;
   PacketRouter packet_router;
   NiceMock<MockRtpRtcpInterface> module;
 
@@ -755,7 +755,7 @@
 }
 
 TEST(PacketRouterRembTest, NonCandidateReceiveRtpModuleNotUsedForRemb) {
-  rtc::ScopedFakeClock clock;
+  ScopedFakeClock clock;
   PacketRouter packet_router;
   NiceMock<MockRtpRtcpInterface> module;
 
@@ -773,7 +773,7 @@
 }
 
 TEST(PacketRouterRembTest, CandidateReceiveRtpModuleUsedForRemb) {
-  rtc::ScopedFakeClock clock;
+  ScopedFakeClock clock;
   PacketRouter packet_router;
   NiceMock<MockRtpRtcpInterface> module;
 
@@ -792,7 +792,7 @@
 
 TEST(PacketRouterRembTest,
      SendCandidatePreferredOverReceiveCandidate_SendModuleAddedFirst) {
-  rtc::ScopedFakeClock clock;
+  ScopedFakeClock clock;
   PacketRouter packet_router;
   NiceMock<MockRtpRtcpInterface> send_module;
   NiceMock<MockRtpRtcpInterface> receive_module;
@@ -819,7 +819,7 @@
 
 TEST(PacketRouterRembTest,
      SendCandidatePreferredOverReceiveCandidate_ReceiveModuleAddedFirst) {
-  rtc::ScopedFakeClock clock;
+  ScopedFakeClock clock;
   PacketRouter packet_router;
   NiceMock<MockRtpRtcpInterface> send_module;
   NiceMock<MockRtpRtcpInterface> receive_module;
@@ -846,7 +846,7 @@
 }
 
 TEST(PacketRouterRembTest, ReceiveModuleTakesOverWhenLastSendModuleRemoved) {
-  rtc::ScopedFakeClock clock;
+  ScopedFakeClock clock;
   PacketRouter packet_router;
   NiceMock<MockRtpRtcpInterface> send_module;
   NiceMock<MockRtpRtcpInterface> receive_module;
diff --git a/modules/video_coding/codecs/vp8/screenshare_layers_unittest.cc b/modules/video_coding/codecs/vp8/screenshare_layers_unittest.cc
index fbcb7d8..2ba7b89 100644
--- a/modules/video_coding/codecs/vp8/screenshare_layers_unittest.cc
+++ b/modules/video_coding/codecs/vp8/screenshare_layers_unittest.cc
@@ -192,7 +192,7 @@
   int min_qp_;
   uint32_t max_qp_;
   int frame_size_;
-  rtc::ScopedFakeClock clock_;
+  ScopedFakeClock clock_;
   std::unique_ptr<ScreenshareLayers> layers_;
 
   uint32_t timestamp_;
diff --git a/p2p/base/p2p_transport_channel_unittest.cc b/p2p/base/p2p_transport_channel_unittest.cc
index 7d89744..c7693af 100644
--- a/p2p/base/p2p_transport_channel_unittest.cc
+++ b/p2p/base/p2p_transport_channel_unittest.cc
@@ -435,7 +435,7 @@
       return ice_regathering_counter_[reason];
     }
 
-    rtc::FakeNetworkManager network_manager_;
+    webrtc::FakeNetworkManager network_manager_;
     std::unique_ptr<BasicPortAllocator> allocator_;
     webrtc::AsyncDnsResolverFactoryInterface* async_dns_resolver_factory_ =
         nullptr;
@@ -710,7 +710,7 @@
   }
 
   void Test(const Environment& env, const Result& expected) {
-    rtc::ScopedFakeClock clock;
+    webrtc::ScopedFakeClock clock;
     int64_t connect_start = rtc::TimeMillis();
     int64_t connect_time;
 
@@ -769,7 +769,7 @@
     DestroyChannels();
   }
 
-  void TestSendRecv(rtc::ThreadProcessingFakeClock* clock) {
+  void TestSendRecv(webrtc::ThreadProcessingFakeClock* clock) {
     for (int i = 0; i < 10; ++i) {
       const char* data = "ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890";
       int len = static_cast<int>(strlen(data));
@@ -805,7 +805,7 @@
   // new connection using the newly generated ice candidates.
   // Before calling this function the end points must be configured.
   void TestHandleIceUfragPasswordChanged() {
-    rtc::ScopedFakeClock clock;
+    webrtc::ScopedFakeClock clock;
     ep1_ch1()->SetRemoteIceParameters(kIceParams[1]);
     ep2_ch1()->SetRemoteIceParameters(kIceParams[0]);
     EXPECT_THAT(
@@ -1347,7 +1347,7 @@
 
 // Test the operation of GetStats.
 TEST_F(P2PTransportChannelTest, GetStats) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   ConfigureEndpoints(env, OPEN, OPEN, kDefaultPortAllocatorFlags,
                      kDefaultPortAllocatorFlags);
@@ -1402,7 +1402,7 @@
 }
 
 TEST_F(P2PTransportChannelTest, GetStatsSwitchConnection) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   IceConfig continual_gathering_config =
       CreateIceConfig(1000, GATHER_CONTINUALLY);
@@ -1484,7 +1484,7 @@
 // change if and only if continual gathering is enabled.
 TEST_F(P2PTransportChannelTest,
        TestIceRegatheringReasonContinualGatheringByNetworkChange) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   ConfigureEndpoints(env, OPEN, OPEN, kOnlyLocalPorts, kOnlyLocalPorts);
 
@@ -1530,7 +1530,7 @@
 // failure if and only if continual gathering is enabled.
 TEST_F(P2PTransportChannelTest,
        TestIceRegatheringReasonContinualGatheringByNetworkFailure) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   ConfigureEndpoints(env, OPEN, OPEN, kOnlyLocalPorts, kOnlyLocalPorts);
 
@@ -1832,7 +1832,7 @@
 
 // Test that if remote candidates don't have ufrag and pwd, we still work.
 TEST_F(P2PTransportChannelTest, RemoteCandidatesWithoutUfragPwd) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   set_remote_ice_parameter_source(FROM_SETICEPARAMETERS);
   ConfigureEndpoints(env, OPEN, OPEN, kDefaultPortAllocatorFlags,
@@ -1859,7 +1859,7 @@
 // Test that a host behind NAT cannot be reached when incoming_only
 // is set to true.
 TEST_F(P2PTransportChannelTest, IncomingOnlyBlocked) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   ConfigureEndpoints(env, NAT_FULL_CONE, OPEN, kDefaultPortAllocatorFlags,
                      kDefaultPortAllocatorFlags);
@@ -1882,7 +1882,7 @@
 // Test that a peer behind NAT can connect to a peer that has
 // incoming_only flag set.
 TEST_F(P2PTransportChannelTest, IncomingOnlyOpen) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   ConfigureEndpoints(env, OPEN, NAT_FULL_CONE, kDefaultPortAllocatorFlags,
                      kDefaultPortAllocatorFlags);
@@ -1929,7 +1929,7 @@
 }
 
 TEST_F(P2PTransportChannelTest, TestTcpConnectionsFromActiveToPassive) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   CreatePortAllocators(env);
   AddAddress(0, kPublicAddrs[0]);
@@ -1982,7 +1982,7 @@
 
 // Test that tcptype is set on all candidates for a connection running over TCP.
 TEST_F(P2PTransportChannelTest, TestTcpConnectionTcptypeSet) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   ConfigureEndpoints(env, BLOCK_UDP_AND_INCOMING_TCP, OPEN,
                      PORTALLOCATOR_ENABLE_SHARED_SOCKET,
@@ -2009,7 +2009,7 @@
 }
 
 TEST_F(P2PTransportChannelTest, TestIceRoleConflict) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   CreatePortAllocators(env);
   AddAddress(0, kPublicAddrs[0]);
@@ -2052,7 +2052,7 @@
 
 // Tests that the ice configs (protocol and role) can be passed down to ports.
 TEST_F(P2PTransportChannelTest, TestIceConfigWillPassDownToPort) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   CreatePortAllocators(env);
   AddAddress(0, kPublicAddrs[0]);
@@ -2120,7 +2120,7 @@
 
 // Verify IPv6 connection is preferred over IPv4.
 TEST_F(P2PTransportChannelTest, TestIPv6Connections) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   CreatePortAllocators(env);
   AddAddress(0, kIPv6PublicAddrs[0]);
@@ -2156,7 +2156,7 @@
 
 // Testing forceful TURN connections.
 TEST_F(P2PTransportChannelTest, TestForceTurn) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   ConfigureEndpoints(
       env, NAT_PORT_RESTRICTED, NAT_SYMMETRIC,
@@ -2191,7 +2191,7 @@
 // Test that if continual gathering is set to true, ICE gathering state will
 // not change to "Complete", and vice versa.
 TEST_F(P2PTransportChannelTest, TestContinualGathering) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   ConfigureEndpoints(env, OPEN, OPEN, kDefaultPortAllocatorFlags,
                      kDefaultPortAllocatorFlags);
@@ -2224,7 +2224,7 @@
 // Test that a connection succeeds when the P2PTransportChannel uses a pooled
 // PortAllocatorSession that has not yet finished gathering candidates.
 TEST_F(P2PTransportChannelTest, TestUsingPooledSessionBeforeDoneGathering) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   ConfigureEndpoints(env, OPEN, OPEN, kDefaultPortAllocatorFlags,
                      kDefaultPortAllocatorFlags);
@@ -2272,7 +2272,7 @@
 // Test that a connection succeeds when the P2PTransportChannel uses a pooled
 // PortAllocatorSession that already finished gathering candidates.
 TEST_F(P2PTransportChannelTest, TestUsingPooledSessionAfterDoneGathering) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   ConfigureEndpoints(env, OPEN, OPEN, kDefaultPortAllocatorFlags,
                      kDefaultPortAllocatorFlags);
@@ -2374,7 +2374,7 @@
 
 // Test that a TURN/peer reflexive candidate pair is also presumed writable.
 TEST_F(P2PTransportChannelTest, TurnToPrflxPresumedWritable) {
-  rtc::ScopedFakeClock fake_clock;
+  webrtc::ScopedFakeClock fake_clock;
   const Environment env = CreateEnvironment();
 
   // We need to add artificial network delay to verify that the connection
@@ -2433,7 +2433,7 @@
 // Test that a presumed-writable TURN<->TURN connection is preferred above an
 // unreliable connection (one that has failed to be pinged for some time).
 TEST_F(P2PTransportChannelTest, PresumedWritablePreferredOverUnreliable) {
-  rtc::ScopedFakeClock fake_clock;
+  webrtc::ScopedFakeClock fake_clock;
   const Environment env = CreateEnvironment();
 
   ConfigureEndpoints(env, NAT_SYMMETRIC, NAT_SYMMETRIC,
@@ -2527,7 +2527,7 @@
 // crbug.com/webrtc/9034.
 TEST_F(P2PTransportChannelTest,
        TurnToPrflxSelectedAfterResolvingIceControllingRoleConflict) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   // Gather only relay candidates.
   ConfigureEndpoints(env, NAT_SYMMETRIC, NAT_SYMMETRIC,
@@ -2574,7 +2574,7 @@
 // acknowledgement in the connectivity check from the remote peer.
 TEST_F(P2PTransportChannelTest,
        CanConnectWithPiggybackCheckAcknowledgementWhenCheckResponseBlocked) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment(FieldTrials::CreateNoGlobal(
       "WebRTC-PiggybackIceCheckAcknowledgement/Enabled/"));
   ConfigureEndpoints(env, OPEN, OPEN, kOnlyLocalPorts, kOnlyLocalPorts);
@@ -2755,7 +2755,7 @@
 // Test that we can quickly switch links if an interface goes down.
 // The controlled side has two interfaces and one will die.
 TEST_F(P2PTransportChannelMultihomedTest, TestFailoverControlledSide) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   CreatePortAllocators(env);
   AddAddress(0, kPublicAddrs[0]);
@@ -2817,7 +2817,7 @@
 // Test that we can quickly switch links if an interface goes down.
 // The controlling side has two interfaces and one will die.
 TEST_F(P2PTransportChannelMultihomedTest, TestFailoverControllingSide) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   CreatePortAllocators(env);
   // Simulate failing over from Wi-Fi to cell interface.
@@ -2867,7 +2867,7 @@
 // Tests that we can quickly switch links if an interface goes down when
 // there are many connections.
 TEST_F(P2PTransportChannelMultihomedTest, TestFailoverWithManyConnections) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   CreatePortAllocators(env);
   test_turn_server()->AddInternalSocket(kTurnTcpIntAddr, webrtc::PROTO_TCP);
@@ -2980,7 +2980,7 @@
 // the nomination of the selected connection on the controlled side will
 // increase.
 TEST_F(P2PTransportChannelMultihomedTest, TestIceRenomination) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   CreatePortAllocators(env);
   // Simulate failing over from Wi-Fi to cell interface.
@@ -3055,7 +3055,7 @@
 // TestFailoverControlledSide and TestFailoverControllingSide.
 TEST_F(P2PTransportChannelMultihomedTest,
        TestConnectionSwitchDampeningControlledSide) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   CreatePortAllocators(env);
   AddAddress(0, kPublicAddrs[0]);
@@ -3124,7 +3124,7 @@
 // the selected connection will not switch.
 TEST_F(P2PTransportChannelMultihomedTest,
        TestConnectionSwitchDampeningControllingSide) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   CreatePortAllocators(env);
   // Simulate failing over from Wi-Fi to cell interface.
@@ -3187,7 +3187,7 @@
 // Tests that if the remote side's network failed, it won't cause the local
 // side to switch connections and networks.
 TEST_F(P2PTransportChannelMultihomedTest, TestRemoteFailover) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   CreatePortAllocators(env);
   // The interface names are chosen so that `cellular` would have higher
@@ -3418,7 +3418,7 @@
 }
 
 TEST_F(P2PTransportChannelMultihomedTest, TestGetState) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   CreatePortAllocators(env);
   AddAddress(0, kAlternateAddrs[0]);
@@ -3448,7 +3448,7 @@
 // will be removed from the port list of the channel, and the respective
 // remote candidates on the other participant will be removed eventually.
 TEST_F(P2PTransportChannelMultihomedTest, TestNetworkBecomesInactive) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   CreatePortAllocators(env);
   AddAddress(0, kPublicAddrs[0]);
@@ -3582,7 +3582,7 @@
 // Tests that we can switch links via continual gathering.
 TEST_F(P2PTransportChannelMultihomedTest,
        TestSwitchLinksViaContinualGathering) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   CreatePortAllocators(env);
   AddAddress(0, kPublicAddrs[0]);
@@ -3642,7 +3642,7 @@
 
 // Tests that the backup connection will be restored after it is destroyed.
 TEST_F(P2PTransportChannelMultihomedTest, TestRestoreBackupConnection) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   CreatePortAllocators(env);
   auto& wifi = kAlternateAddrs;
@@ -3696,7 +3696,7 @@
 }
 
 TEST_F(P2PTransportChannelMultihomedTest, TestVpnDefault) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   CreatePortAllocators(env);
   AddAddress(0, kPublicAddrs[0], "eth0", rtc::ADAPTER_TYPE_ETHERNET);
@@ -3718,7 +3718,7 @@
 }
 
 TEST_F(P2PTransportChannelMultihomedTest, TestVpnPreferVpn) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   CreatePortAllocators(env);
   AddAddress(0, kPublicAddrs[0], "eth0", rtc::ADAPTER_TYPE_ETHERNET);
@@ -3757,7 +3757,7 @@
 }
 
 TEST_F(P2PTransportChannelMultihomedTest, TestVpnAvoidVpn) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   CreatePortAllocators(env);
   AddAddress(0, kPublicAddrs[0], "eth0", rtc::ADAPTER_TYPE_CELLULAR);
@@ -3795,7 +3795,7 @@
 }
 
 TEST_F(P2PTransportChannelMultihomedTest, TestVpnNeverVpn) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   CreatePortAllocators(env);
   AddAddress(0, kPublicAddrs[0], "eth0", rtc::ADAPTER_TYPE_CELLULAR);
@@ -3831,7 +3831,7 @@
 }
 
 TEST_F(P2PTransportChannelMultihomedTest, TestVpnOnlyVpn) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   CreatePortAllocators(env);
   AddAddress(0, kPublicAddrs[0], "eth0", rtc::ADAPTER_TYPE_CELLULAR);
@@ -3866,7 +3866,7 @@
 }
 
 TEST_F(P2PTransportChannelMultihomedTest, StunDictionaryPerformsSync) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   CreatePortAllocators(env);
   AddAddress(0, kPublicAddrs[0], "eth0", rtc::ADAPTER_TYPE_CELLULAR);
@@ -3935,7 +3935,7 @@
       P2PTransportChannel* ch,
       absl::string_view ip,
       int port_num,
-      rtc::ThreadProcessingFakeClock* clock = nullptr) {
+      webrtc::ThreadProcessingFakeClock* clock = nullptr) {
     if (clock == nullptr) {
       EXPECT_THAT(
           webrtc::WaitUntil(
@@ -3995,7 +3995,7 @@
   }
 
   Connection* CreateConnectionWithCandidate(P2PTransportChannel* channel,
-                                            rtc::ScopedFakeClock* clock,
+                                            webrtc::ScopedFakeClock* clock,
                                             absl::string_view ip_addr,
                                             int port,
                                             int priority,
@@ -4201,7 +4201,7 @@
 
 // Verify that the connections are pinged at the right time.
 TEST_F(P2PTransportChannelPingTest, TestStunPingIntervals) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   int RTT_RATIO = 4;
   int SCHEDULING_RANGE = 200;
@@ -4298,7 +4298,7 @@
 // Test that we start pinging as soon as we have a connection and remote ICE
 // parameters.
 TEST_F(P2PTransportChannelPingTest, PingingStartedAsSoonAsPossible) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
 
   FakePortAllocator pa(rtc::Thread::Current(), packet_socket_factory(),
@@ -4540,7 +4540,7 @@
 }
 
 TEST_F(P2PTransportChannelPingTest, TestReceivingStateChange) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   FakePortAllocator pa(rtc::Thread::Current(), packet_socket_factory(),
                        &env.field_trials());
@@ -4967,7 +4967,7 @@
 
 TEST_F(P2PTransportChannelPingTest,
        TestControlledAgentDataReceivingTakesHigherPrecedenceThanPriority) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   clock.AdvanceTime(webrtc::TimeDelta::Seconds(1));
   FakePortAllocator pa(rtc::Thread::Current(), packet_socket_factory(),
@@ -5022,7 +5022,7 @@
 
 TEST_F(P2PTransportChannelPingTest,
        TestControlledAgentNominationTakesHigherPrecedenceThanDataReceiving) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   clock.AdvanceTime(webrtc::TimeDelta::Seconds(1));
   const Environment env = CreateEnvironment();
 
@@ -5067,7 +5067,7 @@
 
 TEST_F(P2PTransportChannelPingTest,
        TestControlledAgentSelectsConnectionWithHigherNomination) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   clock.AdvanceTime(webrtc::TimeDelta::Seconds(1));
   const Environment env = CreateEnvironment();
 
@@ -5118,7 +5118,7 @@
 }
 
 TEST_F(P2PTransportChannelPingTest, TestEstimatedDisconnectedTime) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   clock.AdvanceTime(webrtc::TimeDelta::Seconds(1));
   const Environment env = CreateEnvironment();
 
@@ -5183,7 +5183,7 @@
 
 TEST_F(P2PTransportChannelPingTest,
        TestControlledAgentIgnoresSmallerNomination) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   clock.AdvanceTime(webrtc::TimeDelta::Seconds(1));
   const Environment env = CreateEnvironment();
 
@@ -5204,7 +5204,7 @@
 
 TEST_F(P2PTransportChannelPingTest,
        TestControlledAgentWriteStateTakesHigherPrecedenceThanNomination) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
 
   FakePortAllocator pa(rtc::Thread::Current(), packet_socket_factory(),
@@ -5304,7 +5304,7 @@
 // When the current selected connection is strong, lower-priority connections
 // will be pruned. Otherwise, lower-priority connections are kept.
 TEST_F(P2PTransportChannelPingTest, TestDontPruneWhenWeak) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   clock.AdvanceTime(webrtc::TimeDelta::Seconds(1));
   const Environment env = CreateEnvironment();
   FakePortAllocator pa(rtc::Thread::Current(), packet_socket_factory(),
@@ -5354,7 +5354,7 @@
 }
 
 TEST_F(P2PTransportChannelPingTest, TestDontPruneHighPriorityConnections) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   FakePortAllocator pa(rtc::Thread::Current(), packet_socket_factory(),
                        &env.field_trials());
@@ -5380,7 +5380,7 @@
 
 // Test that GetState returns the state correctly.
 TEST_F(P2PTransportChannelPingTest, TestGetState) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   clock.AdvanceTime(webrtc::TimeDelta::Seconds(1));
   const Environment env = CreateEnvironment();
   FakePortAllocator pa(rtc::Thread::Current(), packet_socket_factory(),
@@ -5432,7 +5432,7 @@
 // Test that when a low-priority connection is pruned, it is not deleted
 // right away, and it can become active and be pruned again.
 TEST_F(P2PTransportChannelPingTest, TestConnectionPrunedAgain) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   clock.AdvanceTime(webrtc::TimeDelta::Seconds(1));
   const Environment env = CreateEnvironment();
 
@@ -5513,7 +5513,7 @@
 // Test that if all connections in a channel has timed out on writing, they
 // will all be deleted. We use Prune to simulate write_time_out.
 TEST_F(P2PTransportChannelPingTest, TestDeleteConnectionsIfAllWriteTimedout) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   FakePortAllocator pa(rtc::Thread::Current(), packet_socket_factory(),
                        &env.field_trials());
@@ -5651,7 +5651,7 @@
 // will be destroyed. The port will only be destroyed after it is marked as
 // "pruned."
 TEST_F(P2PTransportChannelPingTest, TestPortDestroyedAfterTimeoutAndPruned) {
-  rtc::ScopedFakeClock fake_clock;
+  webrtc::ScopedFakeClock fake_clock;
   const Environment env = CreateEnvironment();
 
   FakePortAllocator pa(rtc::Thread::Current(), packet_socket_factory(),
@@ -5777,7 +5777,7 @@
 
  private:
   std::unique_ptr<BasicPortAllocator> port_allocator_;
-  rtc::FakeNetworkManager network_manager_;
+  webrtc::FakeNetworkManager network_manager_;
   webrtc::TestTurnServer turn_server_;
   std::unique_ptr<P2PTransportChannel> channel_;
 };
@@ -6372,7 +6372,7 @@
 
 TEST_F(P2PTransportChannelTest,
        ConnectingIncreasesSelectedCandidatePairChanges) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   ConfigureEndpoints(env, OPEN, OPEN, kDefaultPortAllocatorFlags,
                      kDefaultPortAllocatorFlags);
@@ -6397,7 +6397,7 @@
 
 TEST_F(P2PTransportChannelTest,
        DisconnectedIncreasesSelectedCandidatePairChanges) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   ConfigureEndpoints(env, OPEN, OPEN, kDefaultPortAllocatorFlags,
                      kDefaultPortAllocatorFlags);
@@ -6435,7 +6435,7 @@
 
 TEST_F(P2PTransportChannelTest,
        NewSelectionIncreasesSelectedCandidatePairChanges) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   ConfigureEndpoints(env, OPEN, OPEN, kDefaultPortAllocatorFlags,
                      kDefaultPortAllocatorFlags);
@@ -6658,7 +6658,7 @@
 // removed and are still usable for necessary route switching.
 TEST_F(P2PTransportChannelTest,
        SurfaceHostCandidateOnCandidateFilterChangeFromRelayToAll) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
 
   ConfigureEndpoints(
@@ -6747,7 +6747,7 @@
 // changing the candidate filter.
 TEST_F(P2PTransportChannelTest,
        SurfaceSrflxCandidateOnCandidateFilterChangeFromRelayToNoHost) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   // We need an actual NAT so that the host candidate is not equivalent to the
   // srflx candidate; otherwise, the host candidate would still surface even
@@ -6841,7 +6841,7 @@
 // gathering stopped.
 TEST_F(P2PTransportChannelTest,
        CannotSurfaceTheNewlyAllowedOnFilterChangeIfNotGatheringContinually) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
 
   ConfigureEndpoints(
@@ -6883,7 +6883,7 @@
 // match the filter, are not removed.
 TEST_F(P2PTransportChannelTest,
        RestrictingCandidateFilterDoesNotRemoveRegatheredCandidates) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
 
   ConfigureEndpoints(
@@ -6968,7 +6968,7 @@
 // i.e surface_ice_candidates_on_ice_transport_type_changed requires
 // coordination outside of webrtc to function properly.
 TEST_F(P2PTransportChannelTest, SurfaceRequiresCoordination) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment(FieldTrials::CreateNoGlobal(
       "WebRTC-IceFieldTrials/skip_relay_to_non_relay_connections:true/"));
 
@@ -7049,7 +7049,7 @@
 
 TEST_F(P2PTransportChannelPingTest, TestInitialSelectDampening0) {
   constexpr int kMargin = 10;
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   clock.AdvanceTime(webrtc::TimeDelta::Seconds(1));
   const Environment env = CreateEnvironment(FieldTrials::CreateNoGlobal(
       "WebRTC-IceFieldTrials/initial_select_dampening:0/"));
@@ -7078,7 +7078,7 @@
 
 TEST_F(P2PTransportChannelPingTest, TestInitialSelectDampening) {
   constexpr int kMargin = 10;
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   clock.AdvanceTime(webrtc::TimeDelta::Seconds(1));
   const Environment env = CreateEnvironment(FieldTrials::CreateNoGlobal(
       "WebRTC-IceFieldTrials/initial_select_dampening:100/"));
@@ -7107,7 +7107,7 @@
 
 TEST_F(P2PTransportChannelPingTest, TestInitialSelectDampeningPingReceived) {
   constexpr int kMargin = 10;
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   clock.AdvanceTime(webrtc::TimeDelta::Seconds(1));
   const Environment env = CreateEnvironment(FieldTrials::CreateNoGlobal(
       "WebRTC-IceFieldTrials/initial_select_dampening_ping_received:100/"));
@@ -7137,7 +7137,7 @@
 
 TEST_F(P2PTransportChannelPingTest, TestInitialSelectDampeningBoth) {
   constexpr int kMargin = 10;
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   clock.AdvanceTime(webrtc::TimeDelta::Seconds(1));
   const Environment env = CreateEnvironment(FieldTrials::CreateNoGlobal(
       "WebRTC-IceFieldTrials/"
@@ -7389,7 +7389,7 @@
       std::string("WebRTC-IceFieldTrials/stop_gather_on_strongly_connected:") +
       (stop_gather_on_strongly_connected ? "true/" : "false/");
 
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env =
       CreateEnvironment(FieldTrials::CreateNoGlobal(field_trial));
   // Use local + relay
@@ -7469,7 +7469,7 @@
       std::string("WebRTC-IceFieldTrials/stop_gather_on_strongly_connected:") +
       (stop_gather_on_strongly_connected ? "true/" : "false/");
 
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env =
       CreateEnvironment(FieldTrials::CreateNoGlobal(field_trial));
 
@@ -7548,7 +7548,7 @@
 // Tests no candidates are generated with old ice ufrag/passwd after an ice
 // restart even if continual gathering is enabled.
 TEST_F(P2PTransportChannelTest, TestIceNoOldCandidatesAfterIceRestart) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   const Environment env = CreateEnvironment();
   AddAddress(0, kAlternateAddrs[0]);
   ConfigureEndpoints(env, OPEN, OPEN, kDefaultPortAllocatorFlags,
@@ -7632,7 +7632,7 @@
   void piggyback_data_received(const StunByteStringAttribute* data,
                                const StunByteStringAttribute* ack) {}
 
-  rtc::ScopedFakeClock clock_;
+  webrtc::ScopedFakeClock clock_;
   rtc::Buffer pending_packet_;
 };
 
diff --git a/p2p/base/port_unittest.cc b/p2p/base/port_unittest.cc
index 1e2bf99..246778a 100644
--- a/p2p/base/port_unittest.cc
+++ b/p2p/base/port_unittest.cc
@@ -268,7 +268,7 @@
                                        TestPort* lport,
                                        Connection* rconn,
                                        TestPort* rport,
-                                       rtc::ScopedFakeClock* clock,
+                                       webrtc::ScopedFakeClock* clock,
                                        int64_t ms) {
   lconn->Ping(rtc::TimeMillis());
   ASSERT_THAT(webrtc::WaitUntil(
@@ -970,7 +970,7 @@
                                 bool same_addr1,
                                 bool same_addr2,
                                 bool possible) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   RTC_LOG(LS_INFO) << "Test: " << name1 << " to " << name2 << ": ";
   port1->set_component(cricket::ICE_CANDIDATE_COMPONENT_DEFAULT);
   port2->set_component(cricket::ICE_CANDIDATE_COMPONENT_DEFAULT);
@@ -1739,7 +1739,7 @@
 }
 
 TEST_F(PortTest, TestTcpNoDelay) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   auto port1 = CreateTcpPort(kLocalAddr1);
   port1->SetIceRole(cricket::ICEROLE_CONTROLLING);
   int option_value = -1;
@@ -2253,7 +2253,7 @@
 }
 
 TEST_F(PortTest, TestRoundTripTime) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
 
   auto lport = CreateTestPort(kLocalAddr1, "lfrag", "lpass");
   auto rport = CreateTestPort(kLocalAddr2, "rfrag", "rpass");
@@ -3145,7 +3145,7 @@
 // the default setup where the RTT is deterministically one, which generates an
 // estimate given by `MINIMUM_RTT` = 100.
 TEST_F(PortTest, TestWritableState) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   auto port1 = CreateUdpPort(kLocalAddr1);
   port1->SetIceRole(cricket::ICEROLE_CONTROLLING);
   auto port2 = CreateUdpPort(kLocalAddr2);
@@ -3242,7 +3242,7 @@
 // the default value given by `CONNECTION_WRITE_CONNECT_TIMEOUT` and
 // `CONNECTION_WRITE_CONNECT_FAILURES`.
 TEST_F(PortTest, TestWritableStateWithConfiguredThreshold) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   auto port1 = CreateUdpPort(kLocalAddr1);
   port1->SetIceRole(cricket::ICEROLE_CONTROLLING);
   auto port2 = CreateUdpPort(kLocalAddr2);
@@ -3952,7 +3952,7 @@
 // port will time out after connectivity is lost, if they are not marked as
 // "keep alive until pruned."
 TEST_F(PortTest, TestPortTimeoutIfNotKeptAlive) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   int timeout_delay = 100;
   auto port1 = CreateUdpPort(kLocalAddr1);
   ConnectToSignalDestroyed(port1.get());
@@ -3983,7 +3983,7 @@
 // and destroyed again, ports won't be destroyed until a timeout period passes
 // after the last set of connections are all destroyed.
 TEST_F(PortTest, TestPortTimeoutAfterNewConnectionCreatedAndDestroyed) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   int timeout_delay = 100;
   auto port1 = CreateUdpPort(kLocalAddr1);
   ConnectToSignalDestroyed(port1.get());
@@ -4026,7 +4026,7 @@
 // port will time out after connectivity is lost if they are marked as "keep
 // alive until pruned". They will time out after they are pruned.
 TEST_F(PortTest, TestPortNotTimeoutUntilPruned) {
-  rtc::ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   int timeout_delay = 100;
   auto port1 = CreateUdpPort(kLocalAddr1);
   ConnectToSignalDestroyed(port1.get());
@@ -4148,7 +4148,7 @@
     rport_->PrepareAddress();
   }
 
-  rtc::ScopedFakeClock clock_;
+  webrtc::ScopedFakeClock clock_;
   int num_state_changes_ = 0;
 
   Connection* CreateConnection(IceRole role) {
diff --git a/p2p/base/regathering_controller_unittest.cc b/p2p/base/regathering_controller_unittest.cc
index 79773e7..6b66b90 100644
--- a/p2p/base/regathering_controller_unittest.cc
+++ b/p2p/base/regathering_controller_unittest.cc
@@ -125,7 +125,7 @@
 // still in progress or the continual gathering is not enabled.
 TEST_F(RegatheringControllerTest,
        IceRegatheringDoesNotOccurIfSessionNotCleared) {
-  rtc::ScopedFakeClock clock;
+  ScopedFakeClock clock;
   InitializeAndGatherOnce();  // Session not cleared.
 
   BasicRegatheringController::Config config;
@@ -139,7 +139,7 @@
 }
 
 TEST_F(RegatheringControllerTest, IceRegatheringRepeatsAsScheduled) {
-  rtc::ScopedFakeClock clock;
+  ScopedFakeClock clock;
   InitializeAndGatherOnceWithSessionCleared();
 
   BasicRegatheringController::Config config;
@@ -165,7 +165,7 @@
 // and replaced by a new recurring schedule.
 TEST_F(RegatheringControllerTest,
        ScheduleOfIceRegatheringOnFailedNetworksCanBeReplaced) {
-  rtc::ScopedFakeClock clock;
+  ScopedFakeClock clock;
   InitializeAndGatherOnceWithSessionCleared();
 
   BasicRegatheringController::Config config;
diff --git a/p2p/base/stun_port_unittest.cc b/p2p/base/stun_port_unittest.cc
index ee1662f..3a65d2f 100644
--- a/p2p/base/stun_port_unittest.cc
+++ b/p2p/base/stun_port_unittest.cc
@@ -323,7 +323,7 @@
 
 class FakeClockBase {
  public:
-  rtc::ScopedFakeClock fake_clock;
+  webrtc::ScopedFakeClock fake_clock;
 };
 
 class StunPortTest : public FakeClockBase, public StunPortTestBase {};
diff --git a/p2p/base/stun_request_unittest.cc b/p2p/base/stun_request_unittest.cc
index 8cb8bbe..770d514 100644
--- a/p2p/base/stun_request_unittest.cc
+++ b/p2p/base/stun_request_unittest.cc
@@ -151,7 +151,7 @@
 
 // Test that requests are sent at the right times.
 TEST_F(StunRequestTest, TestBackoff) {
-  rtc::ScopedFakeClock fake_clock;
+  webrtc::ScopedFakeClock fake_clock;
   auto* request = new StunRequestThunker(manager_, this);
   std::unique_ptr<StunMessage> res =
       request->CreateResponseMessage(STUN_BINDING_RESPONSE);
@@ -179,7 +179,7 @@
 
 // Test that we timeout properly if no response is received.
 TEST_F(StunRequestTest, TestTimeout) {
-  rtc::ScopedFakeClock fake_clock;
+  webrtc::ScopedFakeClock fake_clock;
   auto* request = new StunRequestThunker(manager_, this);
   std::unique_ptr<StunMessage> res =
       request->CreateResponseMessage(STUN_BINDING_RESPONSE);
diff --git a/p2p/base/transport_description_factory_unittest.cc b/p2p/base/transport_description_factory_unittest.cc
index ad994eb..a706a88 100644
--- a/p2p/base/transport_description_factory_unittest.cc
+++ b/p2p/base/transport_description_factory_unittest.cc
@@ -42,9 +42,9 @@
         f1_(field_trials_),
         f2_(field_trials_),
         cert1_(webrtc::RTCCertificate::Create(std::unique_ptr<rtc::SSLIdentity>(
-            new rtc::FakeSSLIdentity("User1")))),
+            new webrtc::FakeSSLIdentity("User1")))),
         cert2_(webrtc::RTCCertificate::Create(std::unique_ptr<rtc::SSLIdentity>(
-            new rtc::FakeSSLIdentity("User2")))) {
+            new webrtc::FakeSSLIdentity("User2")))) {
     // By default, certificates are supplied.
     f1_.set_certificate(cert1_);
     f2_.set_certificate(cert2_);
diff --git a/p2p/base/turn_port_unittest.cc b/p2p/base/turn_port_unittest.cc
index c9235e5..fcdfd80 100644
--- a/p2p/base/turn_port_unittest.cc
+++ b/p2p/base/turn_port_unittest.cc
@@ -945,7 +945,7 @@
   }
 
   webrtc::test::ScopedKeyValueConfig field_trials_;
-  rtc::ScopedFakeClock fake_clock_;
+  webrtc::ScopedFakeClock fake_clock_;
   // When a "create port" helper method is called with an IP, we create a
   // Network with that IP and add it to this list. Using a list instead of a
   // vector so that when it grows, pointers aren't invalidated.
diff --git a/p2p/base/wrapping_active_ice_controller_unittest.cc b/p2p/base/wrapping_active_ice_controller_unittest.cc
index 433e4c3..a7902b6 100644
--- a/p2p/base/wrapping_active_ice_controller_unittest.cc
+++ b/p2p/base/wrapping_active_ice_controller_unittest.cc
@@ -46,7 +46,7 @@
 
 using ::rtc::AutoThread;
 using ::rtc::Event;
-using ::rtc::ScopedFakeClock;
+using ::webrtc::ScopedFakeClock;
 using ::webrtc::TimeDelta;
 
 using NiceMockIceController = NiceMock<MockIceController>;
diff --git a/p2p/client/basic_port_allocator_unittest.cc b/p2p/client/basic_port_allocator_unittest.cc
index 1a08137..aa5edf8 100644
--- a/p2p/client/basic_port_allocator_unittest.cc
+++ b/p2p/client/basic_port_allocator_unittest.cc
@@ -512,7 +512,7 @@
   std::unique_ptr<rtc::BasicPacketSocketFactory> nat_socket_factory_;
   webrtc::TestStunServer::StunServerPtr stun_server_;
   webrtc::TestTurnServer turn_server_;
-  rtc::FakeNetworkManager network_manager_;
+  webrtc::FakeNetworkManager network_manager_;
   std::unique_ptr<BasicPortAllocator> allocator_;
   std::unique_ptr<PortAllocatorSession> session_;
   std::vector<webrtc::PortInterface*> ports_;
@@ -526,7 +526,7 @@
 
 class FakeClockBase {
  public:
-  rtc::ScopedFakeClock fake_clock;
+  webrtc::ScopedFakeClock fake_clock;
 };
 
 class BasicPortAllocatorTest : public FakeClockBase,
diff --git a/p2p/dtls/dtls_ice_integrationtest.cc b/p2p/dtls/dtls_ice_integrationtest.cc
index a185fa9..efd54d3 100644
--- a/p2p/dtls/dtls_ice_integrationtest.cc
+++ b/p2p/dtls/dtls_ice_integrationtest.cc
@@ -315,8 +315,8 @@
     ep.dtls->SetLocalCertificate(certificate);
   }
 
-  rtc::ScopedFakeClock fake_clock_;
-  rtc::FakeNetworkManager network_manager_;
+  webrtc::ScopedFakeClock fake_clock_;
+  webrtc::FakeNetworkManager network_manager_;
   std::unique_ptr<rtc::VirtualSocketServer> ss_;
   std::unique_ptr<rtc::BasicPacketSocketFactory> socket_factory_;
   std::unique_ptr<webrtc::NetworkEmulationManager> network_emulation_manager_;
diff --git a/p2p/dtls/dtls_transport_unittest.cc b/p2p/dtls/dtls_transport_unittest.cc
index e2d95f4..ae69627 100644
--- a/p2p/dtls/dtls_transport_unittest.cc
+++ b/p2p/dtls/dtls_transport_unittest.cc
@@ -539,7 +539,7 @@
 
  protected:
   rtc::AutoThread main_thread_;
-  rtc::ScopedFakeClock fake_clock_;
+  webrtc::ScopedFakeClock fake_clock_;
   DtlsTestClient client1_;
   DtlsTestClient client2_;
   bool use_dtls_;
diff --git a/p2p/dtls/fake_dtls_transport.h b/p2p/dtls/fake_dtls_transport.h
index 70b95d0..ece74ed 100644
--- a/p2p/dtls/fake_dtls_transport.h
+++ b/p2p/dtls/fake_dtls_transport.h
@@ -40,14 +40,14 @@
 #include "rtc_base/ssl_stream_adapter.h"
 #include "rtc_base/thread.h"
 
-namespace cricket {
+namespace webrtc {
 
 // Fake DTLS transport which is implemented by wrapping a fake ICE transport.
 // Doesn't interact directly with fake ICE transport for anything other than
 // sending packets.
-class FakeDtlsTransport : public DtlsTransportInternal {
+class FakeDtlsTransport : public cricket::DtlsTransportInternal {
  public:
-  explicit FakeDtlsTransport(FakeIceTransport* ice_transport)
+  explicit FakeDtlsTransport(cricket::FakeIceTransport* ice_transport)
       : ice_transport_(ice_transport),
         transport_name_(ice_transport->transport_name()),
         component_(ice_transport->component()),
@@ -62,7 +62,7 @@
         this, &FakeDtlsTransport::OnNetworkRouteChanged);
   }
 
-  explicit FakeDtlsTransport(std::unique_ptr<FakeIceTransport> ice)
+  explicit FakeDtlsTransport(std::unique_ptr<cricket::FakeIceTransport> ice)
       : owned_ice_transport_(std::move(ice)),
         transport_name_(owned_ice_transport_->transport_name()),
         component_(owned_ice_transport_->component()),
@@ -80,14 +80,15 @@
   // If this constructor is called, a new fake ICE transport will be created,
   // and this FakeDtlsTransport will take the ownership.
   FakeDtlsTransport(const std::string& name, int component)
-      : FakeDtlsTransport(std::make_unique<FakeIceTransport>(name, component)) {
-  }
+      : FakeDtlsTransport(
+            std::make_unique<cricket::FakeIceTransport>(name, component)) {}
   FakeDtlsTransport(const std::string& name,
                     int component,
                     rtc::Thread* network_thread)
-      : FakeDtlsTransport(std::make_unique<FakeIceTransport>(name,
-                                                             component,
-                                                             network_thread)) {}
+      : FakeDtlsTransport(
+            std::make_unique<cricket::FakeIceTransport>(name,
+                                                        component,
+                                                        network_thread)) {}
 
   ~FakeDtlsTransport() override {
     if (dest_ && dest_->dest_ == this) {
@@ -97,7 +98,7 @@
   }
 
   // Get inner fake ICE transport.
-  FakeIceTransport* fake_ice_transport() { return ice_transport_; }
+  cricket::FakeIceTransport* fake_ice_transport() { return ice_transport_; }
 
   // If async, will send packets by "Post"-ing to message queue instead of
   // synchronously "Send"-ing.
@@ -114,7 +115,7 @@
     ice_transport_->SetReceiving(receiving);
     set_receiving(receiving);
   }
-  void SetDtlsState(webrtc::DtlsTransportState state) {
+  void SetDtlsState(DtlsTransportState state) {
     dtls_state_ = state;
     SendDtlsState(this, dtls_state_);
   }
@@ -146,9 +147,10 @@
       if (!dtls_role_) {
         dtls_role_ = std::move(webrtc::SSL_CLIENT);
       }
-      SetDtlsState(webrtc::DtlsTransportState::kConnected);
+      SetDtlsState(DtlsTransportState::kConnected);
       ice_transport_->SetDestination(
-          static_cast<FakeIceTransport*>(dest->ice_transport()), asymmetric);
+          static_cast<cricket::FakeIceTransport*>(dest->ice_transport()),
+          asymmetric);
     } else {
       // Simulates loss of connectivity, by asymmetrically forgetting dest_.
       dest_ = nullptr;
@@ -158,21 +160,21 @@
   }
 
   // Fake DtlsTransportInternal implementation.
-  webrtc::DtlsTransportState dtls_state() const override { return dtls_state_; }
+  DtlsTransportState dtls_state() const override { return dtls_state_; }
   const std::string& transport_name() const override { return transport_name_; }
   int component() const override { return component_; }
   const rtc::SSLFingerprint& dtls_fingerprint() const {
     return dtls_fingerprint_;
   }
-  webrtc::RTCError SetRemoteParameters(absl::string_view alg,
-                                       const uint8_t* digest,
-                                       size_t digest_len,
-                                       std::optional<webrtc::SSLRole> role) {
+  RTCError SetRemoteParameters(absl::string_view alg,
+                               const uint8_t* digest,
+                               size_t digest_len,
+                               std::optional<SSLRole> role) {
     if (role) {
       SetDtlsRole(*role);
     }
     SetRemoteFingerprint(alg, digest, digest_len);
-    return webrtc::RTCError::OK();
+    return RTCError::OK();
   }
   bool SetRemoteFingerprint(absl::string_view alg,
                             const uint8_t* digest,
@@ -181,11 +183,11 @@
         rtc::SSLFingerprint(alg, rtc::MakeArrayView(digest, digest_len));
     return true;
   }
-  bool SetDtlsRole(webrtc::SSLRole role) override {
+  bool SetDtlsRole(SSLRole role) override {
     dtls_role_ = std::move(role);
     return true;
   }
-  bool GetDtlsRole(webrtc::SSLRole* role) const override {
+  bool GetDtlsRole(SSLRole* role) const override {
     if (!dtls_role_) {
       return false;
     }
@@ -193,12 +195,12 @@
     return true;
   }
   bool SetLocalCertificate(
-      const rtc::scoped_refptr<webrtc::RTCCertificate>& certificate) override {
+      const scoped_refptr<RTCCertificate>& certificate) override {
     do_dtls_ = true;
     local_cert_ = certificate;
     return true;
   }
-  void SetRemoteSSLCertificate(rtc::FakeSSLCertificate* cert) {
+  void SetRemoteSSLCertificate(FakeSSLCertificate* cert) {
     remote_cert_ = cert;
   }
   bool IsDtlsActive() const override { return do_dtls_; }
@@ -233,8 +235,7 @@
     return "FakeTlsCipherSuite";
   }
   uint16_t GetSslPeerSignatureAlgorithm() const override { return 0; }
-  rtc::scoped_refptr<webrtc::RTCCertificate> GetLocalCertificate()
-      const override {
+  scoped_refptr<RTCCertificate> GetLocalCertificate() const override {
     return local_cert_;
   }
   std::unique_ptr<rtc::SSLCertChain> GetRemoteSSLCertChain() const override {
@@ -250,14 +251,16 @@
     }
     return do_dtls_;
   }
-  void set_ssl_max_protocol_version(webrtc::SSLProtocolVersion version) {
+  void set_ssl_max_protocol_version(SSLProtocolVersion version) {
     ssl_max_version_ = version;
   }
-  webrtc::SSLProtocolVersion ssl_max_protocol_version() const {
+  SSLProtocolVersion ssl_max_protocol_version() const {
     return ssl_max_version_;
   }
 
-  IceTransportInternal* ice_transport() override { return ice_transport_; }
+  cricket::IceTransportInternal* ice_transport() override {
+    return ice_transport_;
+  }
 
   // PacketTransportInternal implementation, which passes through to fake ICE
   // transport for sending actual packets.
@@ -268,7 +271,7 @@
                  const rtc::PacketOptions& options,
                  int flags) override {
     // We expect only SRTP packets to be sent through this interface.
-    if (flags != PF_SRTP_BYPASS && flags != 0) {
+    if (flags != cricket::PF_SRTP_BYPASS && flags != 0) {
       return -1;
     }
     return ice_transport_->SendPacket(data, len, options, flags);
@@ -314,26 +317,32 @@
     SignalNetworkRouteChanged(network_route);
   }
 
-  FakeIceTransport* ice_transport_;
-  std::unique_ptr<FakeIceTransport> owned_ice_transport_;
+  cricket::FakeIceTransport* ice_transport_;
+  std::unique_ptr<cricket::FakeIceTransport> owned_ice_transport_;
   std::string transport_name_;
   int component_;
   FakeDtlsTransport* dest_ = nullptr;
-  rtc::scoped_refptr<webrtc::RTCCertificate> local_cert_;
-  rtc::FakeSSLCertificate* remote_cert_ = nullptr;
+  scoped_refptr<RTCCertificate> local_cert_;
+  FakeSSLCertificate* remote_cert_ = nullptr;
   bool do_dtls_ = false;
-  webrtc::SSLProtocolVersion ssl_max_version_ = webrtc::SSL_PROTOCOL_DTLS_12;
+  SSLProtocolVersion ssl_max_version_ = webrtc::SSL_PROTOCOL_DTLS_12;
   rtc::SSLFingerprint dtls_fingerprint_;
-  std::optional<webrtc::SSLRole> dtls_role_;
+  std::optional<SSLRole> dtls_role_;
   int crypto_suite_ = webrtc::kSrtpAes128CmSha1_80;
   std::optional<int> ssl_cipher_suite_;
 
-  webrtc::DtlsTransportState dtls_state_ = webrtc::DtlsTransportState::kNew;
+  DtlsTransportState dtls_state_ = DtlsTransportState::kNew;
 
   bool receiving_ = false;
   bool writable_ = false;
 };
 
+}  //  namespace webrtc
+
+// Re-export symbols from the webrtc namespace for backwards compatibility.
+// TODO(bugs.webrtc.org/4222596): Remove once all references are updated.
+namespace cricket {
+using ::webrtc::FakeDtlsTransport;
 }  // namespace cricket
 
 #endif  // P2P_DTLS_FAKE_DTLS_TRANSPORT_H_
diff --git a/pc/channel_unittest.cc b/pc/channel_unittest.cc
index e480a03..b907848 100644
--- a/pc/channel_unittest.cc
+++ b/pc/channel_unittest.cc
@@ -229,10 +229,10 @@
         }
       } else {
         // Confirmed to work with KT_RSA and KT_ECDSA.
-        fake_rtp_dtls_transport1_.reset(new cricket::FakeDtlsTransport(
+        fake_rtp_dtls_transport1_.reset(new webrtc::FakeDtlsTransport(
             "channel1", cricket::ICE_CANDIDATE_COMPONENT_RTP, network_thread_));
         if (!(flags1 & RTCP_MUX)) {
-          fake_rtcp_dtls_transport1_.reset(new cricket::FakeDtlsTransport(
+          fake_rtcp_dtls_transport1_.reset(new webrtc::FakeDtlsTransport(
               "channel1", cricket::ICE_CANDIDATE_COMPONENT_RTCP,
               network_thread_));
         }
@@ -255,10 +255,10 @@
         }
       } else {
         // Confirmed to work with KT_RSA and KT_ECDSA.
-        fake_rtp_dtls_transport2_.reset(new cricket::FakeDtlsTransport(
+        fake_rtp_dtls_transport2_.reset(new webrtc::FakeDtlsTransport(
             "channel2", cricket::ICE_CANDIDATE_COMPONENT_RTP, network_thread_));
         if (!(flags2 & RTCP_MUX)) {
-          fake_rtcp_dtls_transport2_.reset(new cricket::FakeDtlsTransport(
+          fake_rtcp_dtls_transport2_.reset(new webrtc::FakeDtlsTransport(
               "channel2", cricket::ICE_CANDIDATE_COMPONENT_RTCP,
               network_thread_));
         }
@@ -1567,10 +1567,10 @@
       webrtc::PendingTaskSafetyFlag::CreateDetached();
   std::unique_ptr<rtc::Thread> network_thread_keeper_;
   rtc::Thread* network_thread_;
-  std::unique_ptr<cricket::FakeDtlsTransport> fake_rtp_dtls_transport1_;
-  std::unique_ptr<cricket::FakeDtlsTransport> fake_rtcp_dtls_transport1_;
-  std::unique_ptr<cricket::FakeDtlsTransport> fake_rtp_dtls_transport2_;
-  std::unique_ptr<cricket::FakeDtlsTransport> fake_rtcp_dtls_transport2_;
+  std::unique_ptr<webrtc::FakeDtlsTransport> fake_rtp_dtls_transport1_;
+  std::unique_ptr<webrtc::FakeDtlsTransport> fake_rtcp_dtls_transport1_;
+  std::unique_ptr<webrtc::FakeDtlsTransport> fake_rtp_dtls_transport2_;
+  std::unique_ptr<webrtc::FakeDtlsTransport> fake_rtcp_dtls_transport2_;
   std::unique_ptr<webrtc::FakePacketTransport> fake_rtp_packet_transport1_;
   std::unique_ptr<webrtc::FakePacketTransport> fake_rtcp_packet_transport1_;
   std::unique_ptr<webrtc::FakePacketTransport> fake_rtp_packet_transport2_;
diff --git a/pc/data_channel_integrationtest.cc b/pc/data_channel_integrationtest.cc
index b2e60bf..5ceb6b7 100644
--- a/pc/data_channel_integrationtest.cc
+++ b/pc/data_channel_integrationtest.cc
@@ -99,7 +99,7 @@
 // where order of construction is finely controlled.
 // This also ensures peerconnection is closed before switching back to non-fake
 // clock, avoiding other races and DCHECK failures such as in rtp_sender.cc.
-class FakeClockForTest : public rtc::ScopedFakeClock {
+class FakeClockForTest : public ScopedFakeClock {
  protected:
   FakeClockForTest() {
     // Some things use a time of "0" as a special value, so we need to start out
diff --git a/pc/dtls_srtp_transport_integrationtest.cc b/pc/dtls_srtp_transport_integrationtest.cc
index 16108c8..86163f8 100644
--- a/pc/dtls_srtp_transport_integrationtest.cc
+++ b/pc/dtls_srtp_transport_integrationtest.cc
@@ -218,7 +218,7 @@
 
  private:
   rtc::AutoThread main_thread_;
-  rtc::ScopedFakeClock fake_clock_;
+  webrtc::ScopedFakeClock fake_clock_;
   webrtc::test::ScopedKeyValueConfig field_trials_;
 
   std::unique_ptr<cricket::FakeIceTransport> client_ice_transport_;
diff --git a/pc/dtls_srtp_transport_unittest.cc b/pc/dtls_srtp_transport_unittest.cc
index 679ddfe..6f9625b 100644
--- a/pc/dtls_srtp_transport_unittest.cc
+++ b/pc/dtls_srtp_transport_unittest.cc
@@ -37,9 +37,9 @@
 #include "test/gtest.h"
 #include "test/scoped_key_value_config.h"
 
-using cricket::FakeDtlsTransport;
 using cricket::FakeIceTransport;
 using webrtc::DtlsSrtpTransport;
+using ::webrtc::FakeDtlsTransport;
 using webrtc::RtpTransport;
 using webrtc::SrtpTransport;
 
diff --git a/pc/dtls_transport_unittest.cc b/pc/dtls_transport_unittest.cc
index 0eb5a20..7a4cc9c 100644
--- a/pc/dtls_transport_unittest.cc
+++ b/pc/dtls_transport_unittest.cc
@@ -34,7 +34,6 @@
 
 constexpr int kNonsenseCipherSuite = 1234;
 
-using cricket::FakeDtlsTransport;
 using ::testing::ElementsAre;
 
 class TestDtlsTransportObserver : public DtlsTransportObserverInterface {
@@ -65,7 +64,7 @@
   DtlsTransport* transport() { return transport_.get(); }
   DtlsTransportObserverInterface* observer() { return &observer_; }
 
-  void CreateTransport(rtc::FakeSSLCertificate* certificate = nullptr) {
+  void CreateTransport(FakeSSLCertificate* certificate = nullptr) {
     auto cricket_transport = std::make_unique<FakeDtlsTransport>(
         "audio", cricket::ICE_CANDIDATE_COMPONENT_RTP);
     if (certificate) {
@@ -136,7 +135,7 @@
 }
 
 TEST_F(DtlsTransportTest, RoleAppearsOnConnect) {
-  rtc::FakeSSLCertificate fake_certificate("fake data");
+  FakeSSLCertificate fake_certificate("fake data");
   CreateTransport(&fake_certificate);
   transport()->RegisterObserver(observer());
   EXPECT_FALSE(transport()->Information().role());
@@ -150,7 +149,7 @@
 }
 
 TEST_F(DtlsTransportTest, CertificateAppearsOnConnect) {
-  rtc::FakeSSLCertificate fake_certificate("fake data");
+  FakeSSLCertificate fake_certificate("fake data");
   CreateTransport(&fake_certificate);
   transport()->RegisterObserver(observer());
   CompleteDtlsHandshake();
@@ -161,7 +160,7 @@
 }
 
 TEST_F(DtlsTransportTest, CertificateDisappearsOnClose) {
-  rtc::FakeSSLCertificate fake_certificate("fake data");
+  FakeSSLCertificate fake_certificate("fake data");
   CreateTransport(&fake_certificate);
   transport()->RegisterObserver(observer());
   CompleteDtlsHandshake();
diff --git a/pc/dtmf_sender_unittest.cc b/pc/dtmf_sender_unittest.cc
index 9c981cb..ba7560d 100644
--- a/pc/dtmf_sender_unittest.cc
+++ b/pc/dtmf_sender_unittest.cc
@@ -218,7 +218,7 @@
   std::unique_ptr<FakeDtmfObserver> observer_;
   std::unique_ptr<FakeDtmfProvider> provider_;
   rtc::scoped_refptr<DtmfSender> dtmf_;
-  rtc::ScopedFakeClock fake_clock_;
+  webrtc::ScopedFakeClock fake_clock_;
 };
 
 TEST_F(DtmfSenderTest, CanInsertDtmf) {
diff --git a/pc/jsep_transport_controller_unittest.cc b/pc/jsep_transport_controller_unittest.cc
index 045c6e8..a6837dc 100644
--- a/pc/jsep_transport_controller_unittest.cc
+++ b/pc/jsep_transport_controller_unittest.cc
@@ -65,7 +65,7 @@
 
 using cricket::Candidate;
 using cricket::Candidates;
-using cricket::FakeDtlsTransport;
+using ::webrtc::FakeDtlsTransport;
 
 static const int kTimeout = 100;
 static const char kIceUfrag1[] = "u0001";
@@ -634,7 +634,7 @@
       transport_controller_
           ->SetLocalDescription(SdpType::kOffer, description.get(), nullptr)
           .ok());
-  rtc::FakeSSLCertificate fake_certificate("fake_data");
+  FakeSSLCertificate fake_certificate("fake_data");
 
   auto fake_audio_dtls = static_cast<FakeDtlsTransport*>(
       transport_controller_->GetDtlsTransport(kAudioMid1));
diff --git a/pc/jsep_transport_unittest.cc b/pc/jsep_transport_unittest.cc
index 18966b6..12da957 100644
--- a/pc/jsep_transport_unittest.cc
+++ b/pc/jsep_transport_unittest.cc
@@ -128,16 +128,16 @@
     auto ice_internal = std::make_unique<FakeIceTransport>(
         kTransportName, ICE_CANDIDATE_COMPONENT_RTP);
     auto rtp_dtls_transport =
-        std::make_unique<FakeDtlsTransport>(ice_internal.get());
+        std::make_unique<webrtc::FakeDtlsTransport>(ice_internal.get());
     auto ice = CreateIceTransport(std::move(ice_internal));
 
     std::unique_ptr<FakeIceTransport> rtcp_ice_internal;
-    std::unique_ptr<FakeDtlsTransport> rtcp_dtls_transport;
+    std::unique_ptr<webrtc::FakeDtlsTransport> rtcp_dtls_transport;
     if (!rtcp_mux_enabled) {
       rtcp_ice_internal = std::make_unique<FakeIceTransport>(
           kTransportName, ICE_CANDIDATE_COMPONENT_RTCP);
       rtcp_dtls_transport =
-          std::make_unique<FakeDtlsTransport>(rtcp_ice_internal.get());
+          std::make_unique<webrtc::FakeDtlsTransport>(rtcp_ice_internal.get());
     }
     auto rtcp_ice = CreateIceTransport(std::move(rtcp_ice_internal));
 
@@ -289,14 +289,14 @@
   ASSERT_TRUE(role);
   EXPECT_EQ(webrtc::SSL_SERVER,
             role);  // Because remote description was "active".
-  auto fake_dtls =
-      static_cast<FakeDtlsTransport*>(jsep_transport_->rtp_dtls_transport());
+  auto fake_dtls = static_cast<webrtc::FakeDtlsTransport*>(
+      jsep_transport_->rtp_dtls_transport());
   EXPECT_EQ(remote_description.transport_desc.identity_fingerprint->ToString(),
             fake_dtls->dtls_fingerprint().ToString());
 
   if (!rtcp_mux_enabled) {
-    auto fake_rtcp_dtls =
-        static_cast<FakeDtlsTransport*>(jsep_transport_->rtcp_dtls_transport());
+    auto fake_rtcp_dtls = static_cast<webrtc::FakeDtlsTransport*>(
+        jsep_transport_->rtcp_dtls_transport());
     EXPECT_EQ(
         remote_description.transport_desc.identity_fingerprint->ToString(),
         fake_rtcp_dtls->dtls_fingerprint().ToString());
@@ -341,14 +341,14 @@
   ASSERT_TRUE(role);
   EXPECT_EQ(webrtc::SSL_CLIENT,
             role);  // Because remote description was "passive".
-  auto fake_dtls =
-      static_cast<FakeDtlsTransport*>(jsep_transport_->rtp_dtls_transport());
+  auto fake_dtls = static_cast<webrtc::FakeDtlsTransport*>(
+      jsep_transport_->rtp_dtls_transport());
   EXPECT_EQ(remote_description.transport_desc.identity_fingerprint->ToString(),
             fake_dtls->dtls_fingerprint().ToString());
 
   if (!rtcp_mux_enabled) {
-    auto fake_rtcp_dtls =
-        static_cast<FakeDtlsTransport*>(jsep_transport_->rtcp_dtls_transport());
+    auto fake_rtcp_dtls = static_cast<webrtc::FakeDtlsTransport*>(
+        jsep_transport_->rtcp_dtls_transport());
     EXPECT_EQ(
         remote_description.transport_desc.identity_fingerprint->ToString(),
         fake_rtcp_dtls->dtls_fingerprint().ToString());
@@ -1056,10 +1056,10 @@
     jsep_transport1_ = CreateJsepTransport2(/*rtcp_mux_enabled=*/true);
     jsep_transport2_ = CreateJsepTransport2(/*rtcp_mux_enabled=*/true);
 
-    auto fake_dtls1 =
-        static_cast<FakeDtlsTransport*>(jsep_transport1_->rtp_dtls_transport());
-    auto fake_dtls2 =
-        static_cast<FakeDtlsTransport*>(jsep_transport2_->rtp_dtls_transport());
+    auto fake_dtls1 = static_cast<webrtc::FakeDtlsTransport*>(
+        jsep_transport1_->rtp_dtls_transport());
+    auto fake_dtls2 = static_cast<webrtc::FakeDtlsTransport*>(
+        jsep_transport2_->rtp_dtls_transport());
 
     fake_dtls1->fake_ice_transport()->RegisterReceivedPacketCallback(
         this, [&](rtc::PacketTransportInternal* transport,
@@ -1103,10 +1103,10 @@
   }
 
   void ConnectTransport() {
-    auto rtp_dtls_transport1 =
-        static_cast<FakeDtlsTransport*>(jsep_transport1_->rtp_dtls_transport());
-    auto rtp_dtls_transport2 =
-        static_cast<FakeDtlsTransport*>(jsep_transport2_->rtp_dtls_transport());
+    auto rtp_dtls_transport1 = static_cast<webrtc::FakeDtlsTransport*>(
+        jsep_transport1_->rtp_dtls_transport());
+    auto rtp_dtls_transport2 = static_cast<webrtc::FakeDtlsTransport*>(
+        jsep_transport2_->rtp_dtls_transport());
     rtp_dtls_transport1->SetDestination(rtp_dtls_transport2);
   }
 
@@ -1165,10 +1165,10 @@
   recv_encrypted_headers2_.push_back(kHeaderExtensionIDs[1]);
 
   if (use_gcm) {
-    auto fake_dtls1 =
-        static_cast<FakeDtlsTransport*>(jsep_transport1_->rtp_dtls_transport());
-    auto fake_dtls2 =
-        static_cast<FakeDtlsTransport*>(jsep_transport2_->rtp_dtls_transport());
+    auto fake_dtls1 = static_cast<webrtc::FakeDtlsTransport*>(
+        jsep_transport1_->rtp_dtls_transport());
+    auto fake_dtls2 = static_cast<webrtc::FakeDtlsTransport*>(
+        jsep_transport2_->rtp_dtls_transport());
 
     fake_dtls1->SetSrtpCryptoSuite(webrtc::kSrtpAeadAes256Gcm);
     fake_dtls2->SetSrtpCryptoSuite(webrtc::kSrtpAeadAes256Gcm);
diff --git a/pc/legacy_stats_collector_unittest.cc b/pc/legacy_stats_collector_unittest.cc
index bd427dc..96dba2e 100644
--- a/pc/legacy_stats_collector_unittest.cc
+++ b/pc/legacy_stats_collector_unittest.cc
@@ -654,9 +654,9 @@
     }
   }
 
-  void TestCertificateReports(const rtc::FakeSSLIdentity& local_identity,
+  void TestCertificateReports(const FakeSSLIdentity& local_identity,
                               const std::vector<std::string>& local_ders,
-                              const rtc::FakeSSLIdentity& remote_identity,
+                              const FakeSSLIdentity& remote_identity,
                               const std::vector<std::string>& remote_ders) {
     const std::string kTransportName = "transport";
 
@@ -1431,7 +1431,7 @@
   local_ders[2] = "some";
   local_ders[3] = "der";
   local_ders[4] = "values";
-  rtc::FakeSSLIdentity local_identity(DersToPems(local_ders));
+  FakeSSLIdentity local_identity(DersToPems(local_ders));
 
   // Build remote certificate chain
   std::vector<std::string> remote_ders(4);
@@ -1439,7 +1439,7 @@
   remote_ders[1] = "non-";
   remote_ders[2] = "intersecting";
   remote_ders[3] = "set";
-  rtc::FakeSSLIdentity remote_identity(DersToPems(remote_ders));
+  FakeSSLIdentity remote_identity(DersToPems(remote_ders));
 
   TestCertificateReports(local_identity, local_ders, remote_identity,
                          remote_ders);
@@ -1450,11 +1450,11 @@
 TEST_F(LegacyStatsCollectorTest, ChainlessCertificateReportsCreated) {
   // Build local certificate.
   std::string local_der = "This is the local der.";
-  rtc::FakeSSLIdentity local_identity(DerToPem(local_der));
+  FakeSSLIdentity local_identity(DerToPem(local_der));
 
   // Build remote certificate.
   std::string remote_der = "This is somebody else's der.";
-  rtc::FakeSSLIdentity remote_identity(DerToPem(remote_der));
+  FakeSSLIdentity remote_identity(DerToPem(remote_der));
 
   TestCertificateReports(local_identity, std::vector<std::string>(1, local_der),
                          remote_identity,
@@ -1503,13 +1503,13 @@
 TEST_F(LegacyStatsCollectorTest, UnsupportedDigestIgnored) {
   // Build a local certificate.
   std::string local_der = "This is the local der.";
-  rtc::FakeSSLIdentity local_identity(DerToPem(local_der));
+  FakeSSLIdentity local_identity(DerToPem(local_der));
 
   // Build a remote certificate with an unsupported digest algorithm.
   std::string remote_der = "This is somebody else's der.";
-  rtc::FakeSSLCertificate remote_cert(DerToPem(remote_der));
+  FakeSSLCertificate remote_cert(DerToPem(remote_der));
   remote_cert.set_digest_algorithm("foobar");
-  rtc::FakeSSLIdentity remote_identity(remote_cert);
+  FakeSSLIdentity remote_identity(remote_cert);
 
   TestCertificateReports(local_identity, std::vector<std::string>(1, local_der),
                          remote_identity, std::vector<std::string>());
diff --git a/pc/media_session_unittest.cc b/pc/media_session_unittest.cc
index ab11d66..3bbd875 100644
--- a/pc/media_session_unittest.cc
+++ b/pc/media_session_unittest.cc
@@ -543,9 +543,9 @@
     codec_lookup_helper_2_.CodecVendor("")->set_video_codecs(
         MAKE_VECTOR(kVideoCodecs2), MAKE_VECTOR(kVideoCodecs2));
     tdf1_.set_certificate(webrtc::RTCCertificate::Create(
-        std::unique_ptr<rtc::SSLIdentity>(new rtc::FakeSSLIdentity("id1"))));
+        std::unique_ptr<rtc::SSLIdentity>(new webrtc::FakeSSLIdentity("id1"))));
     tdf2_.set_certificate(webrtc::RTCCertificate::Create(
-        std::unique_ptr<rtc::SSLIdentity>(new rtc::FakeSSLIdentity("id2"))));
+        std::unique_ptr<rtc::SSLIdentity>(new webrtc::FakeSSLIdentity("id2"))));
   }
 
   // Create a video StreamParamsVec object with:
@@ -4680,9 +4680,9 @@
     codec_lookup_helper_2_.CodecVendor("")->set_video_codecs(
         MAKE_VECTOR(kVideoCodecs2), MAKE_VECTOR(kVideoCodecs2));
     tdf1_.set_certificate(webrtc::RTCCertificate::Create(
-        std::unique_ptr<rtc::SSLIdentity>(new rtc::FakeSSLIdentity("id1"))));
+        std::unique_ptr<rtc::SSLIdentity>(new webrtc::FakeSSLIdentity("id1"))));
     tdf2_.set_certificate(webrtc::RTCCertificate::Create(
-        std::unique_ptr<rtc::SSLIdentity>(new rtc::FakeSSLIdentity("id2"))));
+        std::unique_ptr<rtc::SSLIdentity>(new webrtc::FakeSSLIdentity("id2"))));
   }
 
  protected:
@@ -4747,7 +4747,7 @@
   webrtc::test::ScopedKeyValueConfig field_trials;
   TransportDescriptionFactory tdf(field_trials);
   tdf.set_certificate(webrtc::RTCCertificate::Create(
-      std::unique_ptr<rtc::SSLIdentity>(new rtc::FakeSSLIdentity("id"))));
+      std::unique_ptr<rtc::SSLIdentity>(new webrtc::FakeSSLIdentity("id"))));
 
   rtc::UniqueRandomIdGenerator ssrc_generator;
   CodecLookupHelperForTesting codec_lookup_helper(field_trials);
@@ -4852,11 +4852,12 @@
   webrtc::test::ScopedKeyValueConfig field_trials;
   TransportDescriptionFactory offer_tdf(field_trials);
   TransportDescriptionFactory answer_tdf(field_trials);
-  offer_tdf.set_certificate(webrtc::RTCCertificate::Create(
-      std::unique_ptr<rtc::SSLIdentity>(new rtc::FakeSSLIdentity("offer_id"))));
+  offer_tdf.set_certificate(
+      webrtc::RTCCertificate::Create(std::unique_ptr<rtc::SSLIdentity>(
+          new webrtc::FakeSSLIdentity("offer_id"))));
   answer_tdf.set_certificate(
       webrtc::RTCCertificate::Create(std::unique_ptr<rtc::SSLIdentity>(
-          new rtc::FakeSSLIdentity("answer_id"))));
+          new webrtc::FakeSSLIdentity("answer_id"))));
   rtc::UniqueRandomIdGenerator ssrc_generator1, ssrc_generator2;
   CodecLookupHelperForTesting offer_codec_lookup_helper(field_trials);
   MediaSessionDescriptionFactory offer_factory(
@@ -5022,10 +5023,10 @@
         codec_lookup_helper_answerer_(field_trials_) {
     tdf_offerer_.set_certificate(
         webrtc::RTCCertificate::Create(std::unique_ptr<rtc::SSLIdentity>(
-            new rtc::FakeSSLIdentity("offer_id"))));
+            new webrtc::FakeSSLIdentity("offer_id"))));
     tdf_answerer_.set_certificate(
         webrtc::RTCCertificate::Create(std::unique_ptr<rtc::SSLIdentity>(
-            new rtc::FakeSSLIdentity("answer_id"))));
+            new webrtc::FakeSSLIdentity("answer_id"))));
   }
 
   void CheckH265Level(const std::vector<Codec>& codecs,
diff --git a/pc/peer_connection_bundle_unittest.cc b/pc/peer_connection_bundle_unittest.cc
index d80b524..4bc41c1 100644
--- a/pc/peer_connection_bundle_unittest.cc
+++ b/pc/peer_connection_bundle_unittest.cc
@@ -86,7 +86,7 @@
 // will use: https://www.w3.org/TR/webrtc/#dom-rtcrtpsender-transport
 // Should also be able to remove GetTransceiversForTesting at that point.
 
-class FakeNetworkManagerWithNoAnyNetwork : public rtc::FakeNetworkManager {
+class FakeNetworkManagerWithNoAnyNetwork : public FakeNetworkManager {
  public:
   std::vector<const rtc::Network*> GetAnyAddressNetworks() override {
     // This function allocates networks that are owned by the
@@ -180,12 +180,12 @@
     return false;
   }
 
-  rtc::FakeNetworkManager* network() { return network_; }
+  FakeNetworkManager* network() { return network_; }
 
-  void set_network(rtc::FakeNetworkManager* network) { network_ = network; }
+  void set_network(FakeNetworkManager* network) { network_ = network; }
 
  private:
-  rtc::FakeNetworkManager* network_;
+  FakeNetworkManager* network_;
 };
 
 class PeerConnectionBundleBaseTest : public ::testing::Test {
diff --git a/pc/peer_connection_encodings_integrationtest.cc b/pc/peer_connection_encodings_integrationtest.cc
index f42ca15..22b8a01 100644
--- a/pc/peer_connection_encodings_integrationtest.cc
+++ b/pc/peer_connection_encodings_integrationtest.cc
@@ -3078,9 +3078,8 @@
 #ifdef RTC_ENABLE_H265
   scoped_refptr<PeerConnectionTestWrapper> CreatePcWithFakeH265(
       std::unique_ptr<FieldTrialsView> field_trials = nullptr) {
-    std::unique_ptr<cricket::FakeWebRtcVideoEncoderFactory>
-        video_encoder_factory =
-            std::make_unique<cricket::FakeWebRtcVideoEncoderFactory>();
+    std::unique_ptr<FakeWebRtcVideoEncoderFactory> video_encoder_factory =
+        std::make_unique<FakeWebRtcVideoEncoderFactory>();
     video_encoder_factory->AddSupportedVideoCodec(
         SdpVideoFormat("H265",
                        {{"profile-id", "1"},
@@ -3088,9 +3087,8 @@
                         {"level-id", "156"},
                         {"tx-mode", "SRST"}},
                        {ScalabilityMode::kL1T1}));
-    std::unique_ptr<cricket::FakeWebRtcVideoDecoderFactory>
-        video_decoder_factory =
-            std::make_unique<cricket::FakeWebRtcVideoDecoderFactory>();
+    std::unique_ptr<FakeWebRtcVideoDecoderFactory> video_decoder_factory =
+        std::make_unique<FakeWebRtcVideoDecoderFactory>();
     video_decoder_factory->AddSupportedVideoCodecType("H265");
     auto pc_wrapper = make_ref_counted<PeerConnectionTestWrapper>(
         "pc", &pss_, background_thread_.get(), background_thread_.get());
@@ -3106,9 +3104,8 @@
   // sendrecv "profile-level-id". The sendrecv one is constrained baseline.
   scoped_refptr<PeerConnectionTestWrapper> CreatePcWithUnidirectionalH264(
       std::unique_ptr<FieldTrialsView> field_trials = nullptr) {
-    std::unique_ptr<cricket::FakeWebRtcVideoEncoderFactory>
-        video_encoder_factory =
-            std::make_unique<cricket::FakeWebRtcVideoEncoderFactory>();
+    std::unique_ptr<FakeWebRtcVideoEncoderFactory> video_encoder_factory =
+        std::make_unique<FakeWebRtcVideoEncoderFactory>();
     SdpVideoFormat h264_constrained_baseline =
         SdpVideoFormat("H264",
                        {{"level-asymmetry-allowed", "1"},
@@ -3122,9 +3119,8 @@
                         {"packetization-mode", "1"},
                         {"profile-level-id", "640034"}},  // sendonly
                        {ScalabilityMode::kL1T1}));
-    std::unique_ptr<cricket::FakeWebRtcVideoDecoderFactory>
-        video_decoder_factory =
-            std::make_unique<cricket::FakeWebRtcVideoDecoderFactory>();
+    std::unique_ptr<FakeWebRtcVideoDecoderFactory> video_decoder_factory =
+        std::make_unique<FakeWebRtcVideoDecoderFactory>();
     video_decoder_factory->AddSupportedVideoCodec(h264_constrained_baseline);
     video_decoder_factory->AddSupportedVideoCodec(
         SdpVideoFormat("H264",
diff --git a/pc/peer_connection_factory_unittest.cc b/pc/peer_connection_factory_unittest.cc
index aaa0417..72d71a8 100644
--- a/pc/peer_connection_factory_unittest.cc
+++ b/pc/peer_connection_factory_unittest.cc
@@ -653,8 +653,7 @@
   rtc::scoped_refptr<FakeVideoTrackSource> source =
       FakeVideoTrackSource::Create(/*is_screencast=*/false);
 
-  cricket::FakeFrameSource frame_source(1280, 720,
-                                        rtc::kNumMicrosecsPerSec / 30);
+  FakeFrameSource frame_source(1280, 720, rtc::kNumMicrosecsPerSec / 30);
 
   ASSERT_TRUE(source.get() != NULL);
   rtc::scoped_refptr<VideoTrackInterface> track(
@@ -706,7 +705,7 @@
 TEST(PeerConnectionFactoryDependenciesTest, UsesPacketSocketFactory) {
   constexpr TimeDelta kWaitTimeout = TimeDelta::Seconds(10);
   auto mock_socket_factory =
-      std::make_unique<NiceMock<rtc::MockPacketSocketFactory>>();
+      std::make_unique<NiceMock<MockPacketSocketFactory>>();
 
   rtc::Event called;
   EXPECT_CALL(*mock_socket_factory, CreateUdpSocket(_, _, _))
diff --git a/pc/peer_connection_histogram_unittest.cc b/pc/peer_connection_histogram_unittest.cc
index 5702a12..de67d8e 100644
--- a/pc/peer_connection_histogram_unittest.cc
+++ b/pc/peer_connection_histogram_unittest.cc
@@ -228,7 +228,7 @@
     deps.async_dns_resolver_factory =
         std::make_unique<NiceMock<MockAsyncDnsResolverFactory>>();
 
-    auto fake_network = std::make_unique<rtc::FakeNetworkManager>();
+    auto fake_network = std::make_unique<FakeNetworkManager>();
     fake_network->set_mdns_responder(
         std::make_unique<FakeMdnsResponder>(rtc::Thread::Current()));
     fake_network->AddInterface(NextLocalAddress());
@@ -246,7 +246,7 @@
   }
 
   WrapperPtr CreatePeerConnectionWithPrivateLocalAddresses() {
-    auto fake_network = std::make_unique<rtc::FakeNetworkManager>();
+    auto fake_network = std::make_unique<FakeNetworkManager>();
     fake_network->AddInterface(NextLocalAddress());
     fake_network->AddInterface(kPrivateLocalAddress);
 
@@ -258,7 +258,7 @@
   }
 
   WrapperPtr CreatePeerConnectionWithPrivateIpv6LocalAddresses() {
-    auto fake_network = std::make_unique<rtc::FakeNetworkManager>();
+    auto fake_network = std::make_unique<FakeNetworkManager>();
     fake_network->AddInterface(NextLocalAddress());
     fake_network->AddInterface(kPrivateIpv6LocalAddress);
 
@@ -284,7 +284,7 @@
     } else {
       // If no network manager is provided, one will be created that uses the
       // host network. This doesn't work on all trybots.
-      auto fake_network = std::make_unique<rtc::FakeNetworkManager>();
+      auto fake_network = std::make_unique<FakeNetworkManager>();
       fake_network->AddInterface(NextLocalAddress());
       pcf_deps.network_manager = std::move(fake_network);
     }
diff --git a/pc/peer_connection_ice_unittest.cc b/pc/peer_connection_ice_unittest.cc
index 261d423..74d2e7d 100644
--- a/pc/peer_connection_ice_unittest.cc
+++ b/pc/peer_connection_ice_unittest.cc
@@ -131,12 +131,12 @@
     return candidates;
   }
 
-  rtc::FakeNetworkManager* network() { return network_; }
+  FakeNetworkManager* network() { return network_; }
 
-  void set_network(rtc::FakeNetworkManager* network) { network_ = network; }
+  void set_network(FakeNetworkManager* network) { network_ = network; }
 
  private:
-  rtc::FakeNetworkManager* network_;
+  FakeNetworkManager* network_;
 };
 
 class PeerConnectionIceBaseTest : public ::testing::Test {
@@ -160,7 +160,7 @@
     pcf_deps.worker_thread = rtc::Thread::Current();
     pcf_deps.signaling_thread = rtc::Thread::Current();
     pcf_deps.socket_factory = &vss_;
-    auto network_manager = std::make_unique<rtc::FakeNetworkManager>();
+    auto network_manager = std::make_unique<FakeNetworkManager>();
     auto* fake_network = network_manager.get();
     pcf_deps.network_manager = std::move(network_manager);
     pcf_deps.adm = FakeAudioCaptureModule::Create();
diff --git a/pc/peer_connection_integrationtest.cc b/pc/peer_connection_integrationtest.cc
index d3a945b..0de455e 100644
--- a/pc/peer_connection_integrationtest.cc
+++ b/pc/peer_connection_integrationtest.cc
@@ -125,7 +125,7 @@
 // where order of construction is finely controlled.
 // This also ensures peerconnection is closed before switching back to non-fake
 // clock, avoiding other races and DCHECK failures such as in rtp_sender.cc.
-class FakeClockForTest : public rtc::ScopedFakeClock {
+class FakeClockForTest : public ScopedFakeClock {
  protected:
   FakeClockForTest() {
     // Some things use a time of "0" as a special value, so we need to start out
diff --git a/pc/peer_connection_rampup_tests.cc b/pc/peer_connection_rampup_tests.cc
index cda8dcb..428ca8c 100644
--- a/pc/peer_connection_rampup_tests.cc
+++ b/pc/peer_connection_rampup_tests.cc
@@ -181,7 +181,7 @@
     pcf_deps.worker_thread = worker_thread_.get();
     pcf_deps.signaling_thread = rtc::Thread::Current();
     pcf_deps.socket_factory = &firewall_socket_server_;
-    auto network_manager = std::make_unique<rtc::FakeNetworkManager>();
+    auto network_manager = std::make_unique<FakeNetworkManager>();
     network_manager->AddInterface(kDefaultLocalAddress);
     pcf_deps.network_manager = std::move(network_manager);
     pcf_deps.adm = FakeAudioCaptureModule::Create();
diff --git a/pc/rtc_stats_collector_unittest.cc b/pc/rtc_stats_collector_unittest.cc
index c0d20e3..2aa66e7 100644
--- a/pc/rtc_stats_collector_unittest.cc
+++ b/pc/rtc_stats_collector_unittest.cc
@@ -147,9 +147,8 @@
         "CERTIFICATE", reinterpret_cast<const unsigned char*>(der.c_str()),
         der.length()));
   }
-  info->certificate =
-      RTCCertificate::Create(std::unique_ptr<rtc::FakeSSLIdentity>(
-          new rtc::FakeSSLIdentity(info->pems)));
+  info->certificate = RTCCertificate::Create(
+      std::unique_ptr<FakeSSLIdentity>(new FakeSSLIdentity(info->pems)));
   // Strip header/footer and newline characters of PEM strings.
   for (size_t i = 0; i < info->pems.size(); ++i) {
     absl::StrReplaceAll({{"-----BEGIN CERTIFICATE-----", ""},
@@ -879,7 +878,7 @@
   }
 
  protected:
-  rtc::ScopedFakeClock fake_clock_;
+  ScopedFakeClock fake_clock_;
   rtc::AutoThread main_thread_;
   rtc::scoped_refptr<FakePeerConnectionForStats> pc_;
   std::unique_ptr<RTCStatsCollectorWrapper> stats_;
@@ -1431,7 +1430,7 @@
 
 TEST_F(RTCStatsCollectorTest, CertificateStatsCache) {
   const char kTransportName[] = "transport";
-  rtc::ScopedFakeClock fake_clock;
+  ScopedFakeClock fake_clock;
 
   pc_->AddVoiceChannel("audio", kTransportName);
 
diff --git a/pc/rtp_sender_receiver_unittest.cc b/pc/rtp_sender_receiver_unittest.cc
index 2b67265..75e9f54 100644
--- a/pc/rtp_sender_receiver_unittest.cc
+++ b/pc/rtp_sender_receiver_unittest.cc
@@ -108,7 +108,7 @@
         media_engine_(std::make_unique<cricket::FakeMediaEngine>()),
         fake_call_(env_, worker_thread_, network_thread_),
         local_stream_(MediaStream::Create(kStreamId1)) {
-    rtp_dtls_transport_ = std::make_unique<cricket::FakeDtlsTransport>(
+    rtp_dtls_transport_ = std::make_unique<FakeDtlsTransport>(
         "fake_dtls_transport", cricket::ICE_CANDIDATE_COMPONENT_RTP);
     rtp_transport_ = CreateDtlsSrtpTransport();
 
@@ -223,7 +223,7 @@
     for (int i = 0; i < num_layers; ++i) {
       ssrcs.push_back(kVideoSsrcSimulcast + i);
     }
-    return cricket::CreateSimStreamParams("cname", ssrcs);
+    return CreateSimStreamParams("cname", ssrcs);
   }
 
   uint32_t CreateVideoRtpSender(const cricket::StreamParams& stream_params) {
@@ -309,8 +309,7 @@
     ssrcs.reserve(num_layers);
     for (int i = 0; i < num_layers; ++i)
       ssrcs.push_back(kVideoSsrcSimulcast + i);
-    cricket::StreamParams stream_params =
-        cricket::CreateSimStreamParams("cname", ssrcs);
+    cricket::StreamParams stream_params = CreateSimStreamParams("cname", ssrcs);
     video_media_receive_channel_->AddRecvStream(stream_params);
     uint32_t primary_ssrc = stream_params.first_ssrc();
 
@@ -523,7 +522,7 @@
       video_bitrate_allocator_factory_;
   std::unique_ptr<cricket::FakeMediaEngine> media_engine_;
   UniqueRandomIdGenerator ssrc_generator_;
-  cricket::FakeCall fake_call_;
+  FakeCall fake_call_;
   std::unique_ptr<cricket::VoiceMediaSendChannelInterface>
       voice_media_send_channel_;
   std::unique_ptr<cricket::VideoMediaSendChannelInterface>
@@ -958,8 +957,7 @@
 
   // Simulate the setLocalDescription call
   std::vector<uint32_t> ssrcs(1, 1);
-  cricket::StreamParams stream_params =
-      cricket::CreateSimStreamParams("cname", ssrcs);
+  cricket::StreamParams stream_params = CreateSimStreamParams("cname", ssrcs);
   voice_media_send_channel()->AddSendStream(stream_params);
   audio_rtp_sender_->SetMediaChannel(
       voice_media_send_channel()->AsVoiceSendChannel());
@@ -1212,8 +1210,7 @@
   ssrcs.reserve(2);
   for (int i = 0; i < 2; ++i)
     ssrcs.push_back(kVideoSsrcSimulcast + i);
-  cricket::StreamParams stream_params =
-      cricket::CreateSimStreamParams("cname", ssrcs);
+  cricket::StreamParams stream_params = CreateSimStreamParams("cname", ssrcs);
   video_media_send_channel()->AddSendStream(stream_params);
   video_rtp_sender_->SetMediaChannel(
       video_media_send_channel()->AsVideoSendChannel());
@@ -1254,8 +1251,7 @@
   ssrcs.reserve(2);
   for (int i = 0; i < 2; ++i)
     ssrcs.push_back(kVideoSsrcSimulcast + i);
-  cricket::StreamParams stream_params =
-      cricket::CreateSimStreamParams("cname", ssrcs);
+  cricket::StreamParams stream_params = CreateSimStreamParams("cname", ssrcs);
   video_media_send_channel()->AddSendStream(stream_params);
   video_rtp_sender_->SetMediaChannel(
       video_media_send_channel()->AsVideoSendChannel());
diff --git a/pc/rtp_transceiver_unittest.cc b/pc/rtp_transceiver_unittest.cc
index 2d6efa6..cacd34a 100644
--- a/pc/rtp_transceiver_unittest.cc
+++ b/pc/rtp_transceiver_unittest.cc
@@ -99,7 +99,7 @@
   const std::string content_name("my_mid");
   auto transceiver = rtc::make_ref_counted<RtpTransceiver>(
       cricket::MediaType::MEDIA_TYPE_AUDIO, context());
-  auto channel1 = std::make_unique<NiceMock<cricket::MockChannelInterface>>();
+  auto channel1 = std::make_unique<NiceMock<MockChannelInterface>>();
   EXPECT_CALL(*channel1, media_type())
       .WillRepeatedly(Return(cricket::MediaType::MEDIA_TYPE_AUDIO));
   EXPECT_CALL(*channel1, mid()).WillRepeatedly(ReturnRef(content_name));
@@ -116,7 +116,7 @@
   transceiver->StopInternal();
   EXPECT_EQ(channel1_ptr, transceiver->channel());
 
-  auto channel2 = std::make_unique<NiceMock<cricket::MockChannelInterface>>();
+  auto channel2 = std::make_unique<NiceMock<MockChannelInterface>>();
   EXPECT_CALL(*channel2, media_type())
       .WillRepeatedly(Return(cricket::MediaType::MEDIA_TYPE_AUDIO));
 
@@ -135,7 +135,7 @@
   const std::string content_name("my_mid");
   auto transceiver = rtc::make_ref_counted<RtpTransceiver>(
       cricket::MediaType::MEDIA_TYPE_VIDEO, context());
-  auto channel = std::make_unique<NiceMock<cricket::MockChannelInterface>>();
+  auto channel = std::make_unique<NiceMock<MockChannelInterface>>();
   EXPECT_CALL(*channel, media_type())
       .WillRepeatedly(Return(cricket::MediaType::MEDIA_TYPE_VIDEO));
   EXPECT_CALL(*channel, mid()).WillRepeatedly(ReturnRef(content_name));
@@ -731,8 +731,7 @@
   EXPECT_CALL(*sender_.get(), SetMediaChannel(_));
   EXPECT_CALL(*sender_.get(), SetTransceiverAsStopped());
   EXPECT_CALL(*sender_.get(), Stop());
-  auto mock_channel =
-      std::make_unique<NiceMock<cricket::MockChannelInterface>>();
+  auto mock_channel = std::make_unique<NiceMock<MockChannelInterface>>();
   auto mock_channel_ptr = mock_channel.get();
   EXPECT_CALL(*mock_channel, SetFirstPacketReceivedCallback(_));
   EXPECT_CALL(*mock_channel, media_type())
@@ -765,8 +764,7 @@
   EXPECT_CALL(*sender_.get(), SetTransceiverAsStopped());
   EXPECT_CALL(*sender_.get(), Stop());
 
-  auto mock_channel =
-      std::make_unique<NiceMock<cricket::MockChannelInterface>>();
+  auto mock_channel = std::make_unique<NiceMock<MockChannelInterface>>();
   auto mock_channel_ptr = mock_channel.get();
   EXPECT_CALL(*mock_channel, SetFirstPacketReceivedCallback(_));
   EXPECT_CALL(*mock_channel, media_type())
diff --git a/pc/sctp_transport_unittest.cc b/pc/sctp_transport_unittest.cc
index 0631e35..b7f318a 100644
--- a/pc/sctp_transport_unittest.cc
+++ b/pc/sctp_transport_unittest.cc
@@ -41,7 +41,6 @@
 
 constexpr int kTestMaxSctpStreams = 1234;
 
-using cricket::FakeDtlsTransport;
 using ::testing::ElementsAre;
 
 namespace {
@@ -221,7 +220,7 @@
   ASSERT_THAT(WaitUntil([&] { return observer_.State(); },
                         ::testing::Eq(SctpTransportState::kConnected)),
               IsRtcOk());
-  static_cast<cricket::FakeDtlsTransport*>(dtls_transport_->internal())
+  static_cast<FakeDtlsTransport*>(dtls_transport_->internal())
       ->SetDtlsState(DtlsTransportState::kClosed);
   ASSERT_THAT(WaitUntil([&] { return observer_.State(); },
                         ::testing::Eq(SctpTransportState::kClosed)),
diff --git a/pc/slow_peer_connection_integration_test.cc b/pc/slow_peer_connection_integration_test.cc
index 28a858f..06716cb 100644
--- a/pc/slow_peer_connection_integration_test.cc
+++ b/pc/slow_peer_connection_integration_test.cc
@@ -62,7 +62,7 @@
 // where order of construction is finely controlled.
 // This also ensures peerconnection is closed before switching back to non-fake
 // clock, avoiding other races and DCHECK failures such as in rtp_sender.cc.
-class FakeClockForTest : public rtc::ScopedFakeClock {
+class FakeClockForTest : public ScopedFakeClock {
  protected:
   FakeClockForTest() {
     // Some things use a time of "0" as a special value, so we need to start out
diff --git a/pc/srtp_session_unittest.cc b/pc/srtp_session_unittest.cc
index 88c92fb..148a0a8 100644
--- a/pc/srtp_session_unittest.cc
+++ b/pc/srtp_session_unittest.cc
@@ -53,7 +53,8 @@
   }
   void TestProtectRtp(int crypto_suite) {
     EXPECT_TRUE(s1_.ProtectRtp(rtp_packet_));
-    EXPECT_EQ(rtp_packet_.size(), rtp_len_ + rtp_auth_tag_len(crypto_suite));
+    EXPECT_EQ(rtp_packet_.size(),
+              rtp_len_ + webrtc::rtp_auth_tag_len(crypto_suite));
     // Check that Protect changed the content (up to the original length).
     EXPECT_NE(0, std::memcmp(kPcmuFrame, rtp_packet_.data(), rtp_len_));
     rtp_len_ = rtp_packet_.size();
@@ -61,7 +62,7 @@
   void TestProtectRtcp(int crypto_suite) {
     EXPECT_TRUE(s1_.ProtectRtcp(rtcp_packet_));
     EXPECT_EQ(rtcp_packet_.size(),
-              rtcp_len_ + 4 + rtcp_auth_tag_len(crypto_suite));
+              rtcp_len_ + 4 + webrtc::rtcp_auth_tag_len(crypto_suite));
     // Check that Protect changed the content (up to the original length).
     EXPECT_NE(0, std::memcmp(kRtcpReport, rtcp_packet_.data(), rtcp_len_));
     rtcp_len_ = rtcp_packet_.size();
@@ -89,40 +90,41 @@
 
 // Test that we can set up the session and keys properly.
 TEST_F(SrtpSessionTest, TestGoodSetup) {
-  EXPECT_TRUE(s1_.SetSend(webrtc::kSrtpAes128CmSha1_80, kTestKey1,
+  EXPECT_TRUE(s1_.SetSend(webrtc::kSrtpAes128CmSha1_80, webrtc::kTestKey1,
                           kEncryptedHeaderExtensionIds));
-  EXPECT_TRUE(s2_.SetReceive(webrtc::kSrtpAes128CmSha1_80, kTestKey1,
+  EXPECT_TRUE(s2_.SetReceive(webrtc::kSrtpAes128CmSha1_80, webrtc::kTestKey1,
                              kEncryptedHeaderExtensionIds));
 }
 
 // Test that we can't change the keys once set.
 TEST_F(SrtpSessionTest, TestBadSetup) {
-  EXPECT_TRUE(s1_.SetSend(webrtc::kSrtpAes128CmSha1_80, kTestKey1,
+  EXPECT_TRUE(s1_.SetSend(webrtc::kSrtpAes128CmSha1_80, webrtc::kTestKey1,
                           kEncryptedHeaderExtensionIds));
-  EXPECT_TRUE(s2_.SetReceive(webrtc::kSrtpAes128CmSha1_80, kTestKey1,
+  EXPECT_TRUE(s2_.SetReceive(webrtc::kSrtpAes128CmSha1_80, webrtc::kTestKey1,
                              kEncryptedHeaderExtensionIds));
-  EXPECT_FALSE(s1_.SetSend(webrtc::kSrtpAes128CmSha1_80, kTestKey2,
+  EXPECT_FALSE(s1_.SetSend(webrtc::kSrtpAes128CmSha1_80, webrtc::kTestKey2,
                            kEncryptedHeaderExtensionIds));
-  EXPECT_FALSE(s2_.SetReceive(webrtc::kSrtpAes128CmSha1_80, kTestKey2,
+  EXPECT_FALSE(s2_.SetReceive(webrtc::kSrtpAes128CmSha1_80, webrtc::kTestKey2,
                               kEncryptedHeaderExtensionIds));
 }
 
 // Test that we fail keys of the wrong length.
 TEST_F(SrtpSessionTest, TestKeysTooShort) {
-  EXPECT_FALSE(s1_.SetSend(webrtc::kSrtpAes128CmSha1_80,
-                           rtc::ZeroOnFreeBuffer<uint8_t>(kTestKey1.data(), 1),
-                           kEncryptedHeaderExtensionIds));
   EXPECT_FALSE(
-      s2_.SetReceive(webrtc::kSrtpAes128CmSha1_80,
-                     rtc::ZeroOnFreeBuffer<uint8_t>(kTestKey1.data(), 1),
-                     kEncryptedHeaderExtensionIds));
+      s1_.SetSend(webrtc::kSrtpAes128CmSha1_80,
+                  rtc::ZeroOnFreeBuffer<uint8_t>(webrtc::kTestKey1.data(), 1),
+                  kEncryptedHeaderExtensionIds));
+  EXPECT_FALSE(s2_.SetReceive(
+      webrtc::kSrtpAes128CmSha1_80,
+      rtc::ZeroOnFreeBuffer<uint8_t>(webrtc::kTestKey1.data(), 1),
+      kEncryptedHeaderExtensionIds));
 }
 
 // Test that we can encrypt and decrypt RTP/RTCP using AES_CM_128_HMAC_SHA1_80.
 TEST_F(SrtpSessionTest, TestProtect_AES_CM_128_HMAC_SHA1_80) {
-  EXPECT_TRUE(s1_.SetSend(webrtc::kSrtpAes128CmSha1_80, kTestKey1,
+  EXPECT_TRUE(s1_.SetSend(webrtc::kSrtpAes128CmSha1_80, webrtc::kTestKey1,
                           kEncryptedHeaderExtensionIds));
-  EXPECT_TRUE(s2_.SetReceive(webrtc::kSrtpAes128CmSha1_80, kTestKey1,
+  EXPECT_TRUE(s2_.SetReceive(webrtc::kSrtpAes128CmSha1_80, webrtc::kTestKey1,
                              kEncryptedHeaderExtensionIds));
   TestProtectRtp(webrtc::kSrtpAes128CmSha1_80);
   TestProtectRtcp(webrtc::kSrtpAes128CmSha1_80);
@@ -132,9 +134,9 @@
 
 // Test that we can encrypt and decrypt RTP/RTCP using AES_CM_128_HMAC_SHA1_32.
 TEST_F(SrtpSessionTest, TestProtect_AES_CM_128_HMAC_SHA1_32) {
-  EXPECT_TRUE(s1_.SetSend(webrtc::kSrtpAes128CmSha1_32, kTestKey1,
+  EXPECT_TRUE(s1_.SetSend(webrtc::kSrtpAes128CmSha1_32, webrtc::kTestKey1,
                           kEncryptedHeaderExtensionIds));
-  EXPECT_TRUE(s2_.SetReceive(webrtc::kSrtpAes128CmSha1_32, kTestKey1,
+  EXPECT_TRUE(s2_.SetReceive(webrtc::kSrtpAes128CmSha1_32, webrtc::kTestKey1,
                              kEncryptedHeaderExtensionIds));
   TestProtectRtp(webrtc::kSrtpAes128CmSha1_32);
   TestProtectRtcp(webrtc::kSrtpAes128CmSha1_32);
@@ -143,7 +145,7 @@
 }
 
 TEST_F(SrtpSessionTest, TestGetSendStreamPacketIndex) {
-  EXPECT_TRUE(s1_.SetSend(webrtc::kSrtpAes128CmSha1_32, kTestKey1,
+  EXPECT_TRUE(s1_.SetSend(webrtc::kSrtpAes128CmSha1_32, webrtc::kTestKey1,
                           kEncryptedHeaderExtensionIds));
   int64_t index;
   EXPECT_TRUE(s1_.ProtectRtp(rtp_packet_, &index));
@@ -154,9 +156,9 @@
 
 // Test that we fail to unprotect if someone tampers with the RTP/RTCP paylaods.
 TEST_F(SrtpSessionTest, TestTamperReject) {
-  EXPECT_TRUE(s1_.SetSend(webrtc::kSrtpAes128CmSha1_80, kTestKey1,
+  EXPECT_TRUE(s1_.SetSend(webrtc::kSrtpAes128CmSha1_80, webrtc::kTestKey1,
                           kEncryptedHeaderExtensionIds));
-  EXPECT_TRUE(s2_.SetReceive(webrtc::kSrtpAes128CmSha1_80, kTestKey1,
+  EXPECT_TRUE(s2_.SetReceive(webrtc::kSrtpAes128CmSha1_80, webrtc::kTestKey1,
                              kEncryptedHeaderExtensionIds));
   TestProtectRtp(webrtc::kSrtpAes128CmSha1_80);
   rtp_packet_.MutableData<uint8_t>()[0] = 0x12;
@@ -175,9 +177,9 @@
 
 // Test that we fail to unprotect if the payloads are not authenticated.
 TEST_F(SrtpSessionTest, TestUnencryptReject) {
-  EXPECT_TRUE(s1_.SetSend(webrtc::kSrtpAes128CmSha1_80, kTestKey1,
+  EXPECT_TRUE(s1_.SetSend(webrtc::kSrtpAes128CmSha1_80, webrtc::kTestKey1,
                           kEncryptedHeaderExtensionIds));
-  EXPECT_TRUE(s2_.SetReceive(webrtc::kSrtpAes128CmSha1_80, kTestKey1,
+  EXPECT_TRUE(s2_.SetReceive(webrtc::kSrtpAes128CmSha1_80, webrtc::kTestKey1,
                              kEncryptedHeaderExtensionIds));
   EXPECT_FALSE(s2_.UnprotectRtp(rtp_packet_));
   EXPECT_METRIC_THAT(
@@ -191,7 +193,7 @@
 
 // Test that we fail when using buffers that are too small.
 TEST_F(SrtpSessionTest, TestBuffersTooSmall) {
-  EXPECT_TRUE(s1_.SetSend(webrtc::kSrtpAes128CmSha1_80, kTestKey1,
+  EXPECT_TRUE(s1_.SetSend(webrtc::kSrtpAes128CmSha1_80, webrtc::kTestKey1,
                           kEncryptedHeaderExtensionIds));
   // This buffer does not have extra capacity which we treat as an error.
   rtc::CopyOnWriteBuffer rtp_packet(rtp_packet_.data(), rtp_packet_.size(),
@@ -209,9 +211,9 @@
   static const uint16_t seqnum_small = 10;
   static const uint16_t replay_window = 1024;
 
-  EXPECT_TRUE(s1_.SetSend(webrtc::kSrtpAes128CmSha1_80, kTestKey1,
+  EXPECT_TRUE(s1_.SetSend(webrtc::kSrtpAes128CmSha1_80, webrtc::kTestKey1,
                           kEncryptedHeaderExtensionIds));
-  EXPECT_TRUE(s2_.SetReceive(webrtc::kSrtpAes128CmSha1_80, kTestKey1,
+  EXPECT_TRUE(s2_.SetReceive(webrtc::kSrtpAes128CmSha1_80, webrtc::kTestKey1,
                              kEncryptedHeaderExtensionIds));
 
   // Initial sequence number.
@@ -258,9 +260,9 @@
 }
 
 TEST_F(SrtpSessionTest, RemoveSsrc) {
-  EXPECT_TRUE(s1_.SetSend(webrtc::kSrtpAes128CmSha1_80, kTestKey1,
+  EXPECT_TRUE(s1_.SetSend(webrtc::kSrtpAes128CmSha1_80, webrtc::kTestKey1,
                           kEncryptedHeaderExtensionIds));
-  EXPECT_TRUE(s2_.SetReceive(webrtc::kSrtpAes128CmSha1_80, kTestKey1,
+  EXPECT_TRUE(s2_.SetReceive(webrtc::kSrtpAes128CmSha1_80, webrtc::kTestKey1,
                              kEncryptedHeaderExtensionIds));
   // Encrypt and decrypt the packet once.
   EXPECT_TRUE(s1_.ProtectRtp(rtp_packet_));
@@ -292,9 +294,9 @@
   // failures when it wraps around with packet loss. Pick your starting
   // sequence number in the lower half of the range for robustness reasons,
   // see packet_sequencer.cc for the code doing so.
-  EXPECT_TRUE(s1_.SetSend(webrtc::kSrtpAes128CmSha1_80, kTestKey1,
+  EXPECT_TRUE(s1_.SetSend(webrtc::kSrtpAes128CmSha1_80, webrtc::kTestKey1,
                           kEncryptedHeaderExtensionIds));
-  EXPECT_TRUE(s2_.SetReceive(webrtc::kSrtpAes128CmSha1_80, kTestKey1,
+  EXPECT_TRUE(s2_.SetReceive(webrtc::kSrtpAes128CmSha1_80, webrtc::kTestKey1,
                              kEncryptedHeaderExtensionIds));
   // Buffers include enough room for the 10 byte SRTP auth tag so we can
   // encrypt in place.
@@ -349,9 +351,9 @@
 }
 
 TEST_F(SrtpSessionTest, ProtectGetPacketIndex) {
-  EXPECT_TRUE(s1_.SetSend(webrtc::kSrtpAes128CmSha1_80, kTestKey1,
+  EXPECT_TRUE(s1_.SetSend(webrtc::kSrtpAes128CmSha1_80, webrtc::kTestKey1,
                           kEncryptedHeaderExtensionIds));
-  EXPECT_TRUE(s2_.SetReceive(webrtc::kSrtpAes128CmSha1_80, kTestKey1,
+  EXPECT_TRUE(s2_.SetReceive(webrtc::kSrtpAes128CmSha1_80, webrtc::kTestKey1,
                              kEncryptedHeaderExtensionIds));
   // Buffers include enough room for the 10 byte SRTP auth tag so we can
   // encrypt in place.
diff --git a/pc/srtp_transport_unittest.cc b/pc/srtp_transport_unittest.cc
index a742fb9..77b0a65 100644
--- a/pc/srtp_transport_unittest.cc
+++ b/pc/srtp_transport_unittest.cc
@@ -33,9 +33,9 @@
 #include "test/gtest.h"
 #include "test/scoped_key_value_config.h"
 
-using rtc::kTestKey1;
-using rtc::kTestKey2;
 using ::webrtc::kSrtpAeadAes128Gcm;
+using ::webrtc::kTestKey1;
+using ::webrtc::kTestKey2;
 
 namespace webrtc {
 // 128 bits key + 96 bits salt.
@@ -129,7 +129,7 @@
 
   void TestSendRecvRtpPacket(int crypto_suite) {
     size_t rtp_len = sizeof(kPcmuFrame);
-    size_t packet_size = rtp_len + rtc::rtp_auth_tag_len(crypto_suite);
+    size_t packet_size = rtp_len + rtp_auth_tag_len(crypto_suite);
     rtc::Buffer rtp_packet_buffer(packet_size);
     char* rtp_packet_data = rtp_packet_buffer.data<char>();
     memcpy(rtp_packet_data, kPcmuFrame, rtp_len);
@@ -182,7 +182,7 @@
 
   void TestSendRecvRtcpPacket(int crypto_suite) {
     size_t rtcp_len = sizeof(::kRtcpReport);
-    size_t packet_size = rtcp_len + 4 + rtc::rtcp_auth_tag_len(crypto_suite);
+    size_t packet_size = rtcp_len + 4 + rtcp_auth_tag_len(crypto_suite);
     rtc::Buffer rtcp_packet_buffer(packet_size);
     char* rtcp_packet_data = rtcp_packet_buffer.data<char>();
     memcpy(rtcp_packet_data, ::kRtcpReport, rtcp_len);
@@ -254,7 +254,7 @@
       int crypto_suite,
       const std::vector<int>& encrypted_header_ids) {
     size_t rtp_len = sizeof(kPcmuFrameWithExtensions);
-    size_t packet_size = rtp_len + rtc::rtp_auth_tag_len(crypto_suite);
+    size_t packet_size = rtp_len + rtp_auth_tag_len(crypto_suite);
     rtc::Buffer rtp_packet_buffer(packet_size);
     char* rtp_packet_data = rtp_packet_buffer.data<char>();
     memcpy(rtp_packet_data, kPcmuFrameWithExtensions, rtp_len);
@@ -448,7 +448,7 @@
 
   // Create a packet and try to send it three times.
   size_t rtp_len = sizeof(kPcmuFrame);
-  size_t packet_size = rtp_len + rtc::rtp_auth_tag_len(kSrtpAeadAes128Gcm);
+  size_t packet_size = rtp_len + rtp_auth_tag_len(kSrtpAeadAes128Gcm);
   rtc::Buffer rtp_packet_buffer(packet_size);
   char* rtp_packet_data = rtp_packet_buffer.data<char>();
   memcpy(rtp_packet_data, kPcmuFrame, rtp_len);
diff --git a/pc/test/integration_test_helpers.cc b/pc/test/integration_test_helpers.cc
index 6aed9b0..04dd26f 100644
--- a/pc/test/integration_test_helpers.cc
+++ b/pc/test/integration_test_helpers.cc
@@ -229,7 +229,7 @@
   RTC_DCHECK(!peer_connection_);
   RTC_DCHECK(!peer_connection_factory_);
 
-  auto network_manager = std::make_unique<rtc::FakeNetworkManager>();
+  auto network_manager = std::make_unique<FakeNetworkManager>();
   fake_network_manager_ = network_manager.get();
   fake_network_manager_->AddInterface(kDefaultLocalAddress);
 
diff --git a/pc/test/integration_test_helpers.h b/pc/test/integration_test_helpers.h
index 6b5828e..968c572 100644
--- a/pc/test/integration_test_helpers.h
+++ b/pc/test/integration_test_helpers.h
@@ -643,9 +643,7 @@
     }
   }
 
-  rtc::FakeNetworkManager* network_manager() const {
-    return fake_network_manager_;
-  }
+  FakeNetworkManager* network_manager() const { return fake_network_manager_; }
 
   FakeRtcEventLogFactory* event_log_factory() const {
     return event_log_factory_;
@@ -1145,7 +1143,7 @@
   std::string debug_name_;
 
   // Network manager is owned by the `peer_connection_factory_`.
-  rtc::FakeNetworkManager* fake_network_manager_ = nullptr;
+  FakeNetworkManager* fake_network_manager_ = nullptr;
   rtc::Thread* network_thread_;
 
   // Reference to the mDNS responder owned by `fake_network_manager_` after set.
diff --git a/pc/test/mock_channel_interface.h b/pc/test/mock_channel_interface.h
index 96dc223..d379f9e 100644
--- a/pc/test/mock_channel_interface.h
+++ b/pc/test/mock_channel_interface.h
@@ -24,7 +24,7 @@
 #include "pc/rtp_transport_internal.h"
 #include "test/gmock.h"
 
-namespace cricket {
+namespace webrtc {
 
 // Mock class for BaseChannel.
 // Use this class in unit tests to avoid dependecy on a specific
@@ -32,26 +32,29 @@
 class MockChannelInterface : public cricket::ChannelInterface {
  public:
   MOCK_METHOD(cricket::MediaType, media_type, (), (const, override));
-  MOCK_METHOD(VideoChannel*, AsVideoChannel, (), (override));
-  MOCK_METHOD(VoiceChannel*, AsVoiceChannel, (), (override));
-  MOCK_METHOD(MediaSendChannelInterface*, media_send_channel, (), (override));
-  MOCK_METHOD(VoiceMediaSendChannelInterface*,
+  MOCK_METHOD(cricket::VideoChannel*, AsVideoChannel, (), (override));
+  MOCK_METHOD(cricket::VoiceChannel*, AsVoiceChannel, (), (override));
+  MOCK_METHOD(cricket::MediaSendChannelInterface*,
+              media_send_channel,
+              (),
+              (override));
+  MOCK_METHOD(cricket::VoiceMediaSendChannelInterface*,
               voice_media_send_channel,
               (),
               (override));
-  MOCK_METHOD(VideoMediaSendChannelInterface*,
+  MOCK_METHOD(cricket::VideoMediaSendChannelInterface*,
               video_media_send_channel,
               (),
               (override));
-  MOCK_METHOD(MediaReceiveChannelInterface*,
+  MOCK_METHOD(cricket::MediaReceiveChannelInterface*,
               media_receive_channel,
               (),
               (override));
-  MOCK_METHOD(VoiceMediaReceiveChannelInterface*,
+  MOCK_METHOD(cricket::VoiceMediaReceiveChannelInterface*,
               voice_media_receive_channel,
               (),
               (override));
-  MOCK_METHOD(VideoMediaReceiveChannelInterface*,
+  MOCK_METHOD(cricket::VideoMediaReceiveChannelInterface*,
               video_media_receive_channel,
               (),
               (override));
@@ -68,31 +71,30 @@
               (override));
   MOCK_METHOD(bool,
               SetLocalContent,
-              (const cricket::MediaContentDescription*,
-               webrtc::SdpType,
-               std::string&),
+              (const cricket::MediaContentDescription*, SdpType, std::string&),
               (override));
   MOCK_METHOD(bool,
               SetRemoteContent,
-              (const cricket::MediaContentDescription*,
-               webrtc::SdpType,
-               std::string&),
+              (const cricket::MediaContentDescription*, SdpType, std::string&),
               (override));
   MOCK_METHOD(bool, SetPayloadTypeDemuxingEnabled, (bool), (override));
-  MOCK_METHOD(const std::vector<StreamParams>&,
+  MOCK_METHOD(const std::vector<cricket::StreamParams>&,
               local_streams,
               (),
               (const, override));
-  MOCK_METHOD(const std::vector<StreamParams>&,
+  MOCK_METHOD(const std::vector<cricket::StreamParams>&,
               remote_streams,
               (),
               (const, override));
-  MOCK_METHOD(bool,
-              SetRtpTransport,
-              (webrtc::RtpTransportInternal*),
-              (override));
+  MOCK_METHOD(bool, SetRtpTransport, (RtpTransportInternal*), (override));
 };
 
+}  //  namespace webrtc
+
+// Re-export symbols from the webrtc namespace for backwards compatibility.
+// TODO(bugs.webrtc.org/4222596): Remove once all references are updated.
+namespace cricket {
+using ::webrtc::MockChannelInterface;
 }  // namespace cricket
 
 #endif  // PC_TEST_MOCK_CHANNEL_INTERFACE_H_
diff --git a/pc/test/srtp_test_util.h b/pc/test/srtp_test_util.h
index ccf455d..ba0c355 100644
--- a/pc/test/srtp_test_util.h
+++ b/pc/test/srtp_test_util.h
@@ -17,7 +17,7 @@
 #include "rtc_base/checks.h"
 #include "rtc_base/ssl_stream_adapter.h"
 
-namespace rtc {
+namespace webrtc {
 
 static const rtc::ZeroOnFreeBuffer<uint8_t> kTestKey1{
     "ABCDEFGHIJKLMNOPQRSTUVWXYZ1234", 30};
@@ -51,6 +51,15 @@
   }
 }
 
+}  //  namespace webrtc
+
+// Re-export symbols from the webrtc namespace for backwards compatibility.
+// TODO(bugs.webrtc.org/4222596): Remove once all references are updated.
+namespace rtc {
+using ::webrtc::kTestKey1;
+using ::webrtc::kTestKey2;
+using ::webrtc::rtcp_auth_tag_len;
+using ::webrtc::rtp_auth_tag_len;
 }  // namespace rtc
 
 #endif  // PC_TEST_SRTP_TEST_UTIL_H_
diff --git a/pc/video_track_unittest.cc b/pc/video_track_unittest.cc
index e75fd03..545a8e0 100644
--- a/pc/video_track_unittest.cc
+++ b/pc/video_track_unittest.cc
@@ -41,7 +41,7 @@
   rtc::AutoThread main_thread_;
   rtc::scoped_refptr<FakeVideoTrackSource> video_track_source_;
   rtc::scoped_refptr<VideoTrack> video_track_;
-  cricket::FakeFrameSource frame_source_;
+  webrtc::FakeFrameSource frame_source_;
 };
 
 // VideoTrack::Create will create an API proxy around the source object.
diff --git a/rtc_base/fake_clock.cc b/rtc_base/fake_clock.cc
index 652a5af..30c6fac 100644
--- a/rtc_base/fake_clock.cc
+++ b/rtc_base/fake_clock.cc
@@ -13,50 +13,50 @@
 #include "rtc_base/checks.h"
 #include "rtc_base/thread.h"
 
-namespace rtc {
+namespace webrtc {
 
 int64_t FakeClock::TimeNanos() const {
-  webrtc::MutexLock lock(&lock_);
+  MutexLock lock(&lock_);
   return time_ns_;
 }
 
-void FakeClock::SetTime(webrtc::Timestamp new_time) {
-  webrtc::MutexLock lock(&lock_);
+void FakeClock::SetTime(Timestamp new_time) {
+  MutexLock lock(&lock_);
   RTC_DCHECK(new_time.us() * 1000 >= time_ns_);
   time_ns_ = new_time.us() * 1000;
 }
 
-void FakeClock::AdvanceTime(webrtc::TimeDelta delta) {
-  webrtc::MutexLock lock(&lock_);
+void FakeClock::AdvanceTime(TimeDelta delta) {
+  MutexLock lock(&lock_);
   time_ns_ += delta.ns();
 }
 
-void ThreadProcessingFakeClock::SetTime(webrtc::Timestamp time) {
+void ThreadProcessingFakeClock::SetTime(Timestamp time) {
   clock_.SetTime(time);
   // If message queues are waiting in a socket select() with a timeout provided
   // by the OS, they should wake up and dispatch all messages that are ready.
-  ThreadManager::ProcessAllMessageQueuesForTesting();
+  rtc::ThreadManager::ProcessAllMessageQueuesForTesting();
 }
 
-void ThreadProcessingFakeClock::AdvanceTime(webrtc::TimeDelta delta) {
+void ThreadProcessingFakeClock::AdvanceTime(TimeDelta delta) {
   clock_.AdvanceTime(delta);
-  ThreadManager::ProcessAllMessageQueuesForTesting();
+  rtc::ThreadManager::ProcessAllMessageQueuesForTesting();
 }
 
 ScopedBaseFakeClock::ScopedBaseFakeClock() {
-  prev_clock_ = SetClockForTesting(this);
+  prev_clock_ = rtc::SetClockForTesting(this);
 }
 
 ScopedBaseFakeClock::~ScopedBaseFakeClock() {
-  SetClockForTesting(prev_clock_);
+  rtc::SetClockForTesting(prev_clock_);
 }
 
 ScopedFakeClock::ScopedFakeClock() {
-  prev_clock_ = SetClockForTesting(this);
+  prev_clock_ = rtc::SetClockForTesting(this);
 }
 
 ScopedFakeClock::~ScopedFakeClock() {
-  SetClockForTesting(prev_clock_);
+  rtc::SetClockForTesting(prev_clock_);
 }
 
-}  // namespace rtc
+}  // namespace webrtc
diff --git a/rtc_base/fake_clock.h b/rtc_base/fake_clock.h
index edb507b..e5c5a79 100644
--- a/rtc_base/fake_clock.h
+++ b/rtc_base/fake_clock.h
@@ -19,13 +19,13 @@
 #include "rtc_base/thread_annotations.h"
 #include "rtc_base/time_utils.h"
 
-namespace rtc {
+namespace webrtc {
 
 // Fake clock for use with unit tests, which does not tick on its own.
 // Starts at time 0.
 //
 // TODO(deadbeef): Unify with webrtc::SimulatedClock.
-class FakeClock : public ClockInterface {
+class FakeClock : public rtc::ClockInterface {
  public:
   FakeClock() = default;
   FakeClock(const FakeClock&) = delete;
@@ -38,20 +38,20 @@
   // Methods that can be used by the test to control the time.
 
   // Should only be used to set a time in the future.
-  void SetTime(webrtc::Timestamp new_time);
+  void SetTime(Timestamp new_time);
 
-  void AdvanceTime(webrtc::TimeDelta delta);
+  void AdvanceTime(TimeDelta delta);
 
  private:
-  mutable webrtc::Mutex lock_;
+  mutable Mutex lock_;
   int64_t time_ns_ RTC_GUARDED_BY(lock_) = 0;
 };
 
-class ThreadProcessingFakeClock : public ClockInterface {
+class ThreadProcessingFakeClock : public rtc::ClockInterface {
  public:
   int64_t TimeNanos() const override { return clock_.TimeNanos(); }
-  void SetTime(webrtc::Timestamp time);
-  void AdvanceTime(webrtc::TimeDelta delta);
+  void SetTime(Timestamp time);
+  void AdvanceTime(TimeDelta delta);
 
  private:
   FakeClock clock_;
@@ -65,7 +65,7 @@
   ~ScopedBaseFakeClock() override;
 
  private:
-  ClockInterface* prev_clock_;
+  rtc::ClockInterface* prev_clock_;
 };
 
 // TODO(srte): Rename this to reflect that it also does thread processing.
@@ -75,9 +75,18 @@
   ~ScopedFakeClock() override;
 
  private:
-  ClockInterface* prev_clock_;
+  rtc::ClockInterface* prev_clock_;
 };
 
+}  //  namespace webrtc
+
+// Re-export symbols from the webrtc namespace for backwards compatibility.
+// TODO(bugs.webrtc.org/4222596): Remove once all references are updated.
+namespace rtc {
+using ::webrtc::FakeClock;
+using ::webrtc::ScopedBaseFakeClock;
+using ::webrtc::ScopedFakeClock;
+using ::webrtc::ThreadProcessingFakeClock;
 }  // namespace rtc
 
 #endif  // RTC_BASE_FAKE_CLOCK_H_
diff --git a/rtc_base/fake_clock_unittest.cc b/rtc_base/fake_clock_unittest.cc
index fc1d510..6597042 100644
--- a/rtc_base/fake_clock_unittest.cc
+++ b/rtc_base/fake_clock_unittest.cc
@@ -12,7 +12,7 @@
 
 #include "test/gtest.h"
 
-namespace rtc {
+namespace webrtc {
 TEST(ScopedFakeClockTest, OverridesGlobalClock) {
   const int64_t kFixedTimeUs = 100000;
   int64_t real_time_us = rtc::TimeMicros();
@@ -21,17 +21,17 @@
     ScopedFakeClock scoped;
     EXPECT_EQ(rtc::TimeMicros(), 0);
 
-    scoped.AdvanceTime(webrtc::TimeDelta::Millis(1));
+    scoped.AdvanceTime(TimeDelta::Millis(1));
     EXPECT_EQ(rtc::TimeMicros(), 1000);
 
-    scoped.SetTime(webrtc::Timestamp::Micros(kFixedTimeUs));
+    scoped.SetTime(Timestamp::Micros(kFixedTimeUs));
     EXPECT_EQ(rtc::TimeMicros(), kFixedTimeUs);
 
-    scoped.AdvanceTime(webrtc::TimeDelta::Millis(1));
+    scoped.AdvanceTime(TimeDelta::Millis(1));
     EXPECT_EQ(rtc::TimeMicros(), kFixedTimeUs + 1000);
   }
 
   EXPECT_NE(rtc::TimeMicros(), kFixedTimeUs + 1000);
   EXPECT_GE(rtc::TimeMicros(), real_time_us);
 }
-}  // namespace rtc
+}  // namespace webrtc
diff --git a/rtc_base/fake_network.h b/rtc_base/fake_network.h
index 8ccc881..bb9cef7 100644
--- a/rtc_base/fake_network.h
+++ b/rtc_base/fake_network.h
@@ -23,45 +23,44 @@
 #include "rtc_base/string_encode.h"
 #include "rtc_base/thread.h"
 
-namespace rtc {
+namespace webrtc {
 
 const int kFakeIPv4NetworkPrefixLength = 24;
 const int kFakeIPv6NetworkPrefixLength = 64;
 
 // Fake network manager that allows us to manually specify the IPs to use.
-class FakeNetworkManager : public NetworkManagerBase {
+class FakeNetworkManager : public rtc::NetworkManagerBase {
  public:
   FakeNetworkManager() {}
 
   struct Iface {
-    webrtc::SocketAddress socket_address;
-    AdapterType adapter_type;
-    std::optional<AdapterType> underlying_vpn_adapter_type;
+    SocketAddress socket_address;
+    rtc::AdapterType adapter_type;
+    std::optional<rtc::AdapterType> underlying_vpn_adapter_type;
   };
   typedef std::vector<Iface> IfaceList;
 
-  void AddInterface(const webrtc::SocketAddress& iface) {
+  void AddInterface(const SocketAddress& iface) {
     // Ensure a unique name for the interface if its name is not given.
     AddInterface(iface, "test" + rtc::ToString(next_index_++));
   }
 
-  void AddInterface(const webrtc::SocketAddress& iface,
-                    absl::string_view if_name) {
-    AddInterface(iface, if_name, ADAPTER_TYPE_UNKNOWN);
+  void AddInterface(const SocketAddress& iface, absl::string_view if_name) {
+    AddInterface(iface, if_name, rtc::ADAPTER_TYPE_UNKNOWN);
   }
 
-  void AddInterface(
-      const webrtc::SocketAddress& iface,
-      absl::string_view if_name,
-      AdapterType type,
-      std::optional<AdapterType> underlying_vpn_adapter_type = std::nullopt) {
-    webrtc::SocketAddress address(if_name, 0);
+  void AddInterface(const SocketAddress& iface,
+                    absl::string_view if_name,
+                    rtc::AdapterType type,
+                    std::optional<rtc::AdapterType>
+                        underlying_vpn_adapter_type = std::nullopt) {
+    SocketAddress address(if_name, 0);
     address.SetResolvedIP(iface.ipaddr());
     ifaces_.push_back({address, type, underlying_vpn_adapter_type});
     DoUpdateNetworks();
   }
 
-  void RemoveInterface(const webrtc::SocketAddress& iface) {
+  void RemoveInterface(const SocketAddress& iface) {
     for (IfaceList::iterator it = ifaces_.begin(); it != ifaces_.end(); ++it) {
       if (it->socket_address.EqualIPs(iface)) {
         ifaces_.erase(it);
@@ -75,24 +74,24 @@
     ++start_count_;
     if (start_count_ == 1) {
       sent_first_update_ = false;
-      Thread::Current()->PostTask([this] { DoUpdateNetworks(); });
+      rtc::Thread::Current()->PostTask([this] { DoUpdateNetworks(); });
     } else if (sent_first_update_) {
-      Thread::Current()->PostTask([this] { SignalNetworksChanged(); });
+      rtc::Thread::Current()->PostTask([this] { SignalNetworksChanged(); });
     }
   }
 
   void StopUpdating() override { --start_count_; }
 
-  using NetworkManagerBase::set_default_local_addresses;
-  using NetworkManagerBase::set_enumeration_permission;
+  using rtc::NetworkManagerBase::set_default_local_addresses;
+  using rtc::NetworkManagerBase::set_enumeration_permission;
 
   // rtc::NetworkManager override.
-  webrtc::MdnsResponderInterface* GetMdnsResponder() const override {
+  MdnsResponderInterface* GetMdnsResponder() const override {
     return mdns_responder_.get();
   }
 
   void set_mdns_responder(
-      std::unique_ptr<webrtc::MdnsResponderInterface> mdns_responder) {
+      std::unique_ptr<MdnsResponderInterface> mdns_responder) {
     mdns_responder_ = std::move(mdns_responder);
   }
 
@@ -100,7 +99,7 @@
   void DoUpdateNetworks() {
     if (start_count_ == 0)
       return;
-    std::vector<std::unique_ptr<Network>> networks;
+    std::vector<std::unique_ptr<rtc::Network>> networks;
     for (IfaceList::iterator it = ifaces_.begin(); it != ifaces_.end(); ++it) {
       int prefix_length = 0;
       if (it->socket_address.ipaddr().family() == AF_INET) {
@@ -108,9 +107,9 @@
       } else if (it->socket_address.ipaddr().family() == AF_INET6) {
         prefix_length = kFakeIPv6NetworkPrefixLength;
       }
-      webrtc::IPAddress prefix =
+      IPAddress prefix =
           webrtc::TruncateIP(it->socket_address.ipaddr(), prefix_length);
-      auto net = std::make_unique<Network>(
+      auto net = std::make_unique<rtc::Network>(
           it->socket_address.hostname(), it->socket_address.hostname(), prefix,
           prefix_length, it->adapter_type);
       if (it->underlying_vpn_adapter_type.has_value()) {
@@ -133,9 +132,17 @@
   int start_count_ = 0;
   bool sent_first_update_ = false;
 
-  std::unique_ptr<webrtc::MdnsResponderInterface> mdns_responder_;
+  std::unique_ptr<MdnsResponderInterface> mdns_responder_;
 };
 
+}  //  namespace webrtc
+
+// Re-export symbols from the webrtc namespace for backwards compatibility.
+// TODO(bugs.webrtc.org/4222596): Remove once all references are updated.
+namespace rtc {
+using ::webrtc::FakeNetworkManager;
+using ::webrtc::kFakeIPv4NetworkPrefixLength;
+using ::webrtc::kFakeIPv6NetworkPrefixLength;
 }  // namespace rtc
 
 #endif  // RTC_BASE_FAKE_NETWORK_H_
diff --git a/rtc_base/fake_ssl_identity.cc b/rtc_base/fake_ssl_identity.cc
index 73c843a..4685915 100644
--- a/rtc_base/fake_ssl_identity.cc
+++ b/rtc_base/fake_ssl_identity.cc
@@ -18,18 +18,18 @@
 #include "rtc_base/checks.h"
 #include "rtc_base/message_digest.h"
 
-namespace rtc {
+namespace webrtc {
 
 FakeSSLCertificate::FakeSSLCertificate(absl::string_view pem_string)
     : pem_string_(pem_string),
-      digest_algorithm_(DIGEST_SHA_1),
+      digest_algorithm_(rtc::DIGEST_SHA_1),
       expiration_time_(-1) {}
 
 FakeSSLCertificate::FakeSSLCertificate(const FakeSSLCertificate&) = default;
 
 FakeSSLCertificate::~FakeSSLCertificate() = default;
 
-std::unique_ptr<SSLCertificate> FakeSSLCertificate::Clone() const {
+std::unique_ptr<rtc::SSLCertificate> FakeSSLCertificate::Clone() const {
   return std::make_unique<FakeSSLCertificate>(*this);
 }
 
@@ -39,8 +39,8 @@
 
 void FakeSSLCertificate::ToDER(Buffer* der_buffer) const {
   std::string der_string;
-  RTC_CHECK(
-      SSLIdentity::PemToDer(kPemTypeCertificate, pem_string_, &der_string));
+  RTC_CHECK(rtc::SSLIdentity::PemToDer(rtc::kPemTypeCertificate, pem_string_,
+                                       &der_string));
   der_buffer->SetData(der_string.c_str(), der_string.size());
 }
 
@@ -75,31 +75,31 @@
     : FakeSSLIdentity(FakeSSLCertificate(pem_string)) {}
 
 FakeSSLIdentity::FakeSSLIdentity(const std::vector<std::string>& pem_strings) {
-  std::vector<std::unique_ptr<SSLCertificate>> certs;
+  std::vector<std::unique_ptr<rtc::SSLCertificate>> certs;
   certs.reserve(pem_strings.size());
   for (const std::string& pem_string : pem_strings) {
     certs.push_back(std::make_unique<FakeSSLCertificate>(pem_string));
   }
-  cert_chain_ = std::make_unique<SSLCertChain>(std::move(certs));
+  cert_chain_ = std::make_unique<rtc::SSLCertChain>(std::move(certs));
 }
 
 FakeSSLIdentity::FakeSSLIdentity(const FakeSSLCertificate& cert)
-    : cert_chain_(std::make_unique<SSLCertChain>(cert.Clone())) {}
+    : cert_chain_(std::make_unique<rtc::SSLCertChain>(cert.Clone())) {}
 
 FakeSSLIdentity::FakeSSLIdentity(const FakeSSLIdentity& o)
     : cert_chain_(o.cert_chain_->Clone()) {}
 
 FakeSSLIdentity::~FakeSSLIdentity() = default;
 
-std::unique_ptr<SSLIdentity> FakeSSLIdentity::CloneInternal() const {
+std::unique_ptr<rtc::SSLIdentity> FakeSSLIdentity::CloneInternal() const {
   return std::make_unique<FakeSSLIdentity>(*this);
 }
 
-const SSLCertificate& FakeSSLIdentity::certificate() const {
+const rtc::SSLCertificate& FakeSSLIdentity::certificate() const {
   return cert_chain_->Get(0);
 }
 
-const SSLCertChain& FakeSSLIdentity::cert_chain() const {
+const rtc::SSLCertChain& FakeSSLIdentity::cert_chain() const {
   return *cert_chain_.get();
 }
 
@@ -113,9 +113,9 @@
   return "";
 }
 
-bool FakeSSLIdentity::operator==(const SSLIdentity& other) const {
+bool FakeSSLIdentity::operator==(const rtc::SSLIdentity& other) const {
   RTC_DCHECK_NOTREACHED();  // Not implemented.
   return false;
 }
 
-}  // namespace rtc
+}  // namespace webrtc
diff --git a/rtc_base/fake_ssl_identity.h b/rtc_base/fake_ssl_identity.h
index 2b4ae2e..856b6dc 100644
--- a/rtc_base/fake_ssl_identity.h
+++ b/rtc_base/fake_ssl_identity.h
@@ -18,9 +18,9 @@
 #include "rtc_base/ssl_certificate.h"
 #include "rtc_base/ssl_identity.h"
 
-namespace rtc {
+namespace webrtc {
 
-class FakeSSLCertificate : public SSLCertificate {
+class FakeSSLCertificate : public rtc::SSLCertificate {
  public:
   // SHA-1 is the default digest algorithm because it is available in all build
   // configurations used for unit testing.
@@ -30,7 +30,7 @@
   ~FakeSSLCertificate() override;
 
   // SSLCertificate implementation.
-  std::unique_ptr<SSLCertificate> Clone() const override;
+  std::unique_ptr<rtc::SSLCertificate> Clone() const override;
   std::string ToPEMString() const override;
   void ToDER(Buffer* der_buffer) const override;
   int64_t CertificateExpirationTime() const override;
@@ -51,7 +51,7 @@
   int64_t expiration_time_;
 };
 
-class FakeSSLIdentity : public SSLIdentity {
+class FakeSSLIdentity : public rtc::SSLIdentity {
  public:
   explicit FakeSSLIdentity(absl::string_view pem_string);
   // For a certificate chain.
@@ -63,21 +63,28 @@
   ~FakeSSLIdentity() override;
 
   // SSLIdentity implementation.
-  const SSLCertificate& certificate() const override;
-  const SSLCertChain& cert_chain() const override;
+  const rtc::SSLCertificate& certificate() const override;
+  const rtc::SSLCertChain& cert_chain() const override;
   // Not implemented.
   std::string PrivateKeyToPEMString() const override;
   // Not implemented.
   std::string PublicKeyToPEMString() const override;
   // Not implemented.
-  virtual bool operator==(const SSLIdentity& other) const;
+  virtual bool operator==(const rtc::SSLIdentity& other) const;
 
  private:
-  std::unique_ptr<SSLIdentity> CloneInternal() const override;
+  std::unique_ptr<rtc::SSLIdentity> CloneInternal() const override;
 
-  std::unique_ptr<SSLCertChain> cert_chain_;
+  std::unique_ptr<rtc::SSLCertChain> cert_chain_;
 };
 
+}  //  namespace webrtc
+
+// Re-export symbols from the webrtc namespace for backwards compatibility.
+// TODO(bugs.webrtc.org/4222596): Remove once all references are updated.
+namespace rtc {
+using ::webrtc::FakeSSLCertificate;
+using ::webrtc::FakeSSLIdentity;
 }  // namespace rtc
 
 #endif  // RTC_BASE_FAKE_SSL_IDENTITY_H_
diff --git a/rtc_base/ssl_identity_unittest.cc b/rtc_base/ssl_identity_unittest.cc
index 19b3957..3923619 100644
--- a/rtc_base/ssl_identity_unittest.cc
+++ b/rtc_base/ssl_identity_unittest.cc
@@ -177,7 +177,7 @@
         "CERTIFICATE", reinterpret_cast<const unsigned char*>(der.c_str()),
         der.length()));
   }
-  info.identity.reset(new rtc::FakeSSLIdentity(info.pems));
+  info.identity.reset(new webrtc::FakeSSLIdentity(info.pems));
   // Strip header/footer and newline characters of PEM strings.
   for (size_t i = 0; i < info.pems.size(); ++i) {
     absl::StrReplaceAll({{"-----BEGIN CERTIFICATE-----", ""},
diff --git a/rtc_base/ssl_stream_adapter_unittest.cc b/rtc_base/ssl_stream_adapter_unittest.cc
index 255615e..e020095 100644
--- a/rtc_base/ssl_stream_adapter_unittest.cc
+++ b/rtc_base/ssl_stream_adapter_unittest.cc
@@ -878,7 +878,7 @@
   }
 
   rtc::AutoThread main_thread_;
-  rtc::ScopedFakeClock clock_;
+  webrtc::ScopedFakeClock clock_;
   std::string client_cert_pem_;
   std::string client_private_key_pem_;
   rtc::KeyParams client_key_type_;
diff --git a/rtc_base/test_client.cc b/rtc_base/test_client.cc
index a003599..99acf19 100644
--- a/rtc_base/test_client.cc
+++ b/rtc_base/test_client.cc
@@ -38,7 +38,7 @@
     : TestClient(std::move(socket), nullptr) {}
 
 TestClient::TestClient(std::unique_ptr<rtc::AsyncPacketSocket> socket,
-                       rtc::ThreadProcessingFakeClock* fake_clock)
+                       ThreadProcessingFakeClock* fake_clock)
     : fake_clock_(fake_clock), socket_(std::move(socket)) {
   socket_->RegisterReceivedPacketCallback(
       [&](rtc::AsyncPacketSocket* socket, const rtc::ReceivedPacket& packet) {
diff --git a/rtc_base/test_client.h b/rtc_base/test_client.h
index 5adc108..8f2f25e 100644
--- a/rtc_base/test_client.h
+++ b/rtc_base/test_client.h
@@ -47,7 +47,7 @@
   // for a packet to be received, and thus it needs to advance the fake clock
   // if the test is using one, rather than just sleeping.
   TestClient(std::unique_ptr<rtc::AsyncPacketSocket> socket,
-             rtc::ThreadProcessingFakeClock* fake_clock);
+             ThreadProcessingFakeClock* fake_clock);
   ~TestClient() override;
 
   TestClient(const TestClient&) = delete;
@@ -101,7 +101,7 @@
   bool CheckTimestamp(std::optional<Timestamp> packet_timestamp);
   void AdvanceTime(int ms);
 
-  rtc::ThreadProcessingFakeClock* fake_clock_ = nullptr;
+  ThreadProcessingFakeClock* fake_clock_ = nullptr;
   Mutex mutex_;
   std::unique_ptr<rtc::AsyncPacketSocket> socket_;
   std::vector<std::unique_ptr<Packet>> packets_;
diff --git a/rtc_base/thread_unittest.cc b/rtc_base/thread_unittest.cc
index 3184061..ee885b5 100644
--- a/rtc_base/thread_unittest.cc
+++ b/rtc_base/thread_unittest.cc
@@ -492,7 +492,7 @@
 }
 
 static void DelayedPostsWithIdenticalTimesAreProcessedInFifoOrder(
-    FakeClock& clock,
+    webrtc::FakeClock& clock,
     Thread& q) {
   std::vector<int> run_order;
 
@@ -515,7 +515,7 @@
 }
 
 TEST(ThreadTest, DelayedPostsWithIdenticalTimesAreProcessedInFifoOrder) {
-  ScopedBaseFakeClock clock;
+  webrtc::ScopedBaseFakeClock clock;
   Thread q(CreateDefaultSocketServer(), true);
   q.Start();
   DelayedPostsWithIdenticalTimesAreProcessedInFifoOrder(clock, q);
@@ -804,7 +804,7 @@
 }
 
 TEST(ThreadPostDelayedTaskTest, InvokesInDelayOrder) {
-  ScopedFakeClock clock;
+  webrtc::ScopedFakeClock clock;
   std::unique_ptr<rtc::Thread> background_thread(rtc::Thread::Create());
   background_thread->Start();
 
diff --git a/rtc_base/time_utils_unittest.cc b/rtc_base/time_utils_unittest.cc
index c60c333..6771f03 100644
--- a/rtc_base/time_utils_unittest.cc
+++ b/rtc_base/time_utils_unittest.cc
@@ -160,7 +160,7 @@
 // Test that all the time functions exposed by TimeUtils get time from the
 // fake clock when it's set.
 TEST(FakeClock, TimeFunctionsUseFakeClock) {
-  FakeClock clock;
+  webrtc::FakeClock clock;
   SetClockForTesting(&clock);
 
   clock.SetTime(webrtc::Timestamp::Micros(987654));
@@ -176,12 +176,12 @@
 }
 
 TEST(FakeClock, InitialTime) {
-  FakeClock clock;
+  webrtc::FakeClock clock;
   EXPECT_EQ(0, clock.TimeNanos());
 }
 
 TEST(FakeClock, SetTime) {
-  FakeClock clock;
+  webrtc::FakeClock clock;
   clock.SetTime(webrtc::Timestamp::Micros(123));
   EXPECT_EQ(123000, clock.TimeNanos());
   clock.SetTime(webrtc::Timestamp::Micros(456));
@@ -189,7 +189,7 @@
 }
 
 TEST(FakeClock, AdvanceTime) {
-  FakeClock clock;
+  webrtc::FakeClock clock;
   clock.AdvanceTime(webrtc::TimeDelta::Micros(1u));
   EXPECT_EQ(1000, clock.TimeNanos());
   clock.AdvanceTime(webrtc::TimeDelta::Micros(2222u));
@@ -207,7 +207,7 @@
 TEST(FakeClock, SettingTimeWakesThreads) {
   int64_t real_start_time_ms = TimeMillis();
 
-  ThreadProcessingFakeClock clock;
+  webrtc::ThreadProcessingFakeClock clock;
   SetClockForTesting(&clock);
 
   std::unique_ptr<Thread> worker(Thread::CreateWithSocketServer());
diff --git a/rtc_base/virtual_socket_server.cc b/rtc_base/virtual_socket_server.cc
index ebac6b0..3305be7 100644
--- a/rtc_base/virtual_socket_server.cc
+++ b/rtc_base/virtual_socket_server.cc
@@ -657,7 +657,8 @@
 
 VirtualSocketServer::VirtualSocketServer() : VirtualSocketServer(nullptr) {}
 
-VirtualSocketServer::VirtualSocketServer(ThreadProcessingFakeClock* fake_clock)
+VirtualSocketServer::VirtualSocketServer(
+    webrtc::ThreadProcessingFakeClock* fake_clock)
     : fake_clock_(fake_clock),
       msg_queue_(nullptr),
       stop_on_idle_(false),
diff --git a/rtc_base/virtual_socket_server.h b/rtc_base/virtual_socket_server.h
index 9c7f2c3..5e86e2a 100644
--- a/rtc_base/virtual_socket_server.h
+++ b/rtc_base/virtual_socket_server.h
@@ -226,7 +226,7 @@
   // This constructor needs to be used if the test uses a fake clock and
   // ProcessMessagesUntilIdle, since ProcessMessagesUntilIdle needs a way of
   // advancing time.
-  explicit VirtualSocketServer(ThreadProcessingFakeClock* fake_clock);
+  explicit VirtualSocketServer(webrtc::ThreadProcessingFakeClock* fake_clock);
   ~VirtualSocketServer() override;
 
   VirtualSocketServer(const VirtualSocketServer&) = delete;
@@ -443,7 +443,7 @@
 
   // May be null if the test doesn't use a fake clock, or it does but doesn't
   // use ProcessMessagesUntilIdle.
-  ThreadProcessingFakeClock* fake_clock_ = nullptr;
+  webrtc::ThreadProcessingFakeClock* fake_clock_ = nullptr;
 
   // Used to implement Wait/WakeUp.
   Event wakeup_;
diff --git a/rtc_base/virtual_socket_unittest.cc b/rtc_base/virtual_socket_unittest.cc
index fd8186d..8d24fbc 100644
--- a/rtc_base/virtual_socket_unittest.cc
+++ b/rtc_base/virtual_socket_unittest.cc
@@ -839,7 +839,7 @@
   }
 
  protected:
-  rtc::ScopedFakeClock fake_clock_;
+  webrtc::ScopedFakeClock fake_clock_;
   VirtualSocketServer ss_;
   AutoSocketServerThread thread_;
   const webrtc::SocketAddress kIPv4AnyAddress;
diff --git a/test/fuzzers/utils/rtp_replayer.cc b/test/fuzzers/utils/rtp_replayer.cc
index e5d26f2..2e11936 100644
--- a/test/fuzzers/utils/rtp_replayer.cc
+++ b/test/fuzzers/utils/rtp_replayer.cc
@@ -47,7 +47,7 @@
     const uint8_t* rtp_dump_data,
     size_t rtp_dump_size) {
   RunLoop loop;
-  rtc::ScopedBaseFakeClock fake_clock;
+  ScopedBaseFakeClock fake_clock;
 
   // Work around: webrtc calls webrtc::Random(clock.TimeInMicroseconds())
   // everywhere and Random expects non-zero seed. Let's set the clock non-zero
@@ -149,7 +149,7 @@
 }
 
 void RtpReplayer::ReplayPackets(
-    rtc::FakeClock* clock,
+    FakeClock* clock,
     Call* call,
     test::RtpFileReader* rtp_reader,
     const RtpPacketReceived::ExtensionManager& extensions) {
diff --git a/test/fuzzers/utils/rtp_replayer.h b/test/fuzzers/utils/rtp_replayer.h
index 73220ee..f13b7b7 100644
--- a/test/fuzzers/utils/rtp_replayer.h
+++ b/test/fuzzers/utils/rtp_replayer.h
@@ -79,7 +79,7 @@
       size_t rtp_dump_size);
 
   // Replays each packet to from the RtpDump.
-  static void ReplayPackets(rtc::FakeClock* clock,
+  static void ReplayPackets(FakeClock* clock,
                             Call* call,
                             test::RtpFileReader* rtp_reader,
                             const RtpHeaderExtensionMap& extensions);
diff --git a/test/time_controller/simulated_time_controller.h b/test/time_controller/simulated_time_controller.h
index bd76331..c070146 100644
--- a/test/time_controller/simulated_time_controller.h
+++ b/test/time_controller/simulated_time_controller.h
@@ -154,7 +154,7 @@
   void Unregister(sim_time_impl::SimulatedSequenceRunner* runner);
 
  private:
-  rtc::ScopedBaseFakeClock global_clock_;
+  ScopedBaseFakeClock global_clock_;
   // Provides simulated CurrentNtpInMilliseconds()
   SimulatedClock sim_clock_;
   sim_time_impl::SimulatedTimeControllerImpl impl_;
diff --git a/test/wait_until.h b/test/wait_until.h
index f6d5729..ea2a437 100644
--- a/test/wait_until.h
+++ b/test/wait_until.h
@@ -29,8 +29,8 @@
 
 using ClockVariant = absl::variant<absl::monostate,
                                    SimulatedClock*,
-                                   rtc::FakeClock*,
-                                   rtc::ThreadProcessingFakeClock*,
+                                   FakeClock*,
+                                   ThreadProcessingFakeClock*,
                                    TimeController*>;
 
 namespace wait_until_internal {
diff --git a/test/wait_until_unittest.cc b/test/wait_until_unittest.cc
index fffce70..b6c5bad 100644
--- a/test/wait_until_unittest.cc
+++ b/test/wait_until_unittest.cc
@@ -89,7 +89,7 @@
 }
 
 TEST(WaitUntilTest, ReturnsWhenConditionIsMetWithThreadProcessingFakeClock) {
-  rtc::ScopedFakeClock fake_clock;
+  ScopedFakeClock fake_clock;
 
   int counter = 0;
   RTCErrorOr<int> result =
@@ -101,7 +101,7 @@
 }
 
 TEST(WaitUntilTest, ReturnsWhenConditionIsMetWithFakeClock) {
-  rtc::FakeClock fake_clock;
+  FakeClock fake_clock;
 
   int counter = 0;
   RTCErrorOr<int> result =
diff --git a/video/adaptation/overuse_frame_detector_unittest.cc b/video/adaptation/overuse_frame_detector_unittest.cc
index b1abdd3..92554db 100644
--- a/video/adaptation/overuse_frame_detector_unittest.cc
+++ b/video/adaptation/overuse_frame_detector_unittest.cc
@@ -231,7 +231,7 @@
   }
 
   CpuOveruseOptions options_;
-  rtc::ScopedFakeClock clock_;
+  ScopedFakeClock clock_;
   MockCpuOveruseObserver mock_observer_;
   OveruseFrameDetectorObserverInterface* observer_;
   std::unique_ptr<OveruseFrameDetectorUnderTest> overuse_detector_;
diff --git a/video/encoder_overshoot_detector_unittest.cc b/video/encoder_overshoot_detector_unittest.cc
index 95d0fd1..c85a379 100644
--- a/video/encoder_overshoot_detector_unittest.cc
+++ b/video/encoder_overshoot_detector_unittest.cc
@@ -100,7 +100,7 @@
 
   static constexpr int64_t kWindowSizeMs = 3000;
   EncoderOvershootDetector detector_;
-  rtc::ScopedFakeClock clock_;
+  ScopedFakeClock clock_;
   DataRate target_bitrate_;
   double target_framerate_fps_;
 };
diff --git a/video/send_statistics_proxy_unittest.cc b/video/send_statistics_proxy_unittest.cc
index 5a1147b..d70074f 100644
--- a/video/send_statistics_proxy_unittest.cc
+++ b/video/send_statistics_proxy_unittest.cc
@@ -458,7 +458,7 @@
   // This test relies on rtc::ScopedFakeClock to synchronize these two clocks.
   // TODO(https://crbug.com/webrtc/10640): When the RateTracker uses a Clock
   // this test can stop relying on rtc::ScopedFakeClock.
-  rtc::ScopedFakeClock fake_global_clock;
+  ScopedFakeClock fake_global_clock;
   fake_global_clock.SetTime(
       Timestamp::Millis(fake_clock_.TimeInMilliseconds()));
 
@@ -489,7 +489,7 @@
 TEST_F(SendStatisticsProxyTest, EncodeFrameRateInSubStream) {
   const int kInterframeDelayMs = 100;
   const auto ssrc = config_.rtp.ssrcs[0];
-  rtc::ScopedFakeClock fake_global_clock;
+  ScopedFakeClock fake_global_clock;
   fake_global_clock.SetTime(
       Timestamp::Millis(fake_clock_.TimeInMilliseconds()));
 
@@ -513,7 +513,7 @@
 
 TEST_F(SendStatisticsProxyTest, EncodeFrameRateInSubStreamsVp8Simulcast) {
   const int kInterframeDelayMs = 100;
-  rtc::ScopedFakeClock fake_global_clock;
+  ScopedFakeClock fake_global_clock;
   fake_global_clock.SetTime(
       Timestamp::Millis(fake_clock_.TimeInMilliseconds()));
   EncodedImage encoded_image;
@@ -574,7 +574,7 @@
 
 TEST_F(SendStatisticsProxyTest, EncodeFrameRateInSubStreamsVp9Svc) {
   const int kInterframeDelayMs = 100;
-  rtc::ScopedFakeClock fake_global_clock;
+  ScopedFakeClock fake_global_clock;
   fake_global_clock.SetTime(
       Timestamp::Millis(fake_clock_.TimeInMilliseconds()));
   EncodedImage encoded_image;
diff --git a/video/video_receive_stream2_unittest.cc b/video/video_receive_stream2_unittest.cc
index 0331699..1583323 100644
--- a/video/video_receive_stream2_unittest.cc
+++ b/video/video_receive_stream2_unittest.cc
@@ -268,7 +268,7 @@
   internal::CallStats call_stats_;
   testing::NiceMock<MockVideoDecoder> mock_decoder_;
   FakeVideoRenderer fake_renderer_;
-  cricket::FakeCall fake_call_;
+  FakeCall fake_call_;
   MockTransport mock_transport_;
   test::RtcpPacketParser rtcp_packet_parser_;
   PacketRouter packet_router_;