Move all files in p2p/test to webrtc namespace

This includes files,

- nat_types
- stun_server
- fake_port_allocator
- nat_socket_factory
- fake_ice_transport
- nat_server
- mock_ice_transport
- test_stun_server
- mock_ice_agent
- turn_server
- test_turn_server
- mock_dns_resolving_packet_socket_factory
- fake_packet_transport
- test_turn_customizer
- mock_active_ice_controller
- mock_ice_controller

Bug: webrtc:42232595
Change-Id: I054f8953093102b921627f4bb896eafd663dad7e
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/381060
Commit-Queue: Evan Shrubsole <eshr@webrtc.org>
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@{#44119}
diff --git a/examples/stunserver/stunserver_main.cc b/examples/stunserver/stunserver_main.cc
index ad5d070..ec90361 100644
--- a/examples/stunserver/stunserver_main.cc
+++ b/examples/stunserver/stunserver_main.cc
@@ -15,7 +15,7 @@
 #include "rtc_base/socket_server.h"
 #include "rtc_base/thread.h"
 
-using cricket::StunServer;
+using ::webrtc::StunServer;
 
 int main(int argc, char* argv[]) {
   if (argc != 2) {
diff --git a/examples/turnserver/turnserver_main.cc b/examples/turnserver/turnserver_main.cc
index de8f2de..dd90ac5 100644
--- a/examples/turnserver/turnserver_main.cc
+++ b/examples/turnserver/turnserver_main.cc
@@ -28,7 +28,7 @@
 namespace {
 const char kSoftware[] = "libjingle TurnServer";
 
-class TurnFileAuth : public cricket::TurnAuthInterface {
+class TurnFileAuth : public webrtc::TurnAuthInterface {
  public:
   explicit TurnFileAuth(std::map<std::string, std::string> name_to_key)
       : name_to_key_(std::move(name_to_key)) {}
@@ -80,7 +80,7 @@
     return 1;
   }
 
-  cricket::TurnServer server(&main);
+  webrtc::TurnServer server(&main);
   std::fstream auth_file(argv[4], std::fstream::in);
 
   TurnFileAuth auth(auth_file.is_open()
diff --git a/p2p/base/p2p_transport_channel_unittest.cc b/p2p/base/p2p_transport_channel_unittest.cc
index 7b94134..7d89744 100644
--- a/p2p/base/p2p_transport_channel_unittest.cc
+++ b/p2p/base/p2p_transport_channel_unittest.cc
@@ -158,12 +158,12 @@
 static const SocketAddress kCascadedPrivateAddrs[2] = {
     SocketAddress("192.168.10.11", 0), SocketAddress("192.168.20.22", 0)};
 // The address of the public STUN server.
-static const SocketAddress kStunAddr("99.99.99.1", cricket::STUN_SERVER_PORT);
+static const SocketAddress kStunAddr("99.99.99.1", webrtc::STUN_SERVER_PORT);
 // The addresses for the public turn server.
 static const SocketAddress kTurnUdpIntAddr("99.99.99.3",
-                                           cricket::STUN_SERVER_PORT);
+                                           webrtc::STUN_SERVER_PORT);
 static const SocketAddress kTurnTcpIntAddr("99.99.99.4",
-                                           cricket::STUN_SERVER_PORT + 1);
+                                           webrtc::STUN_SERVER_PORT + 1);
 static const SocketAddress kTurnUdpExtAddr("99.99.99.5", 0);
 static const cricket::RelayCredentials kRelayCredentials("test", "test");
 
@@ -316,11 +316,12 @@
  public:
   P2PTransportChannelTestBase()
       : vss_(new rtc::VirtualSocketServer()),
-        nss_(new rtc::NATSocketServer(vss_.get())),
+        nss_(new webrtc::NATSocketServer(vss_.get())),
         ss_(new rtc::FirewallSocketServer(nss_.get())),
         socket_factory_(new rtc::BasicPacketSocketFactory(ss_.get())),
         main_(ss_.get()),
-        stun_server_(TestStunServer::Create(ss_.get(), kStunAddr, main_)),
+        stun_server_(
+            webrtc::TestStunServer::Create(ss_.get(), kStunAddr, main_)),
         turn_server_(&main_, ss_.get(), kTurnUdpIntAddr, kTurnUdpExtAddr),
         force_relay_(false) {
     ep1_.role_ = ICEROLE_CONTROLLING;
@@ -545,7 +546,7 @@
   P2PTransportChannel* ep2_ch1() { return ep2_.cd1_.ch_.get(); }
   P2PTransportChannel* ep2_ch2() { return ep2_.cd2_.ch_.get(); }
 
-  TestTurnServer* test_turn_server() { return &turn_server_; }
+  webrtc::TestTurnServer* test_turn_server() { return &turn_server_; }
   rtc::VirtualSocketServer* virtual_socket_server() { return vss_.get(); }
 
   // Common results.
@@ -564,7 +565,7 @@
   static const Result kLocalTcpToPrflxTcp;
   static const Result kPrflxTcpToLocalTcp;
 
-  rtc::NATSocketServer* nat() { return nss_.get(); }
+  webrtc::NATSocketServer* nat() { return nss_.get(); }
   rtc::FirewallSocketServer* fw() { return ss_.get(); }
 
   Endpoint* GetEndpoint(int endpoint) {
@@ -1044,15 +1045,15 @@
 
  private:
   std::unique_ptr<rtc::VirtualSocketServer> vss_;
-  std::unique_ptr<rtc::NATSocketServer> nss_;
+  std::unique_ptr<webrtc::NATSocketServer> nss_;
   std::unique_ptr<rtc::FirewallSocketServer> ss_;
   std::unique_ptr<rtc::BasicPacketSocketFactory> socket_factory_;
 
   rtc::AutoSocketServerThread main_;
   rtc::scoped_refptr<PendingTaskSafetyFlag> safety_ =
       PendingTaskSafetyFlag::Create();
-  TestStunServer::StunServerPtr stun_server_;
-  TestTurnServer turn_server_;
+  webrtc::TestStunServer::StunServerPtr stun_server_;
+  webrtc::TestTurnServer turn_server_;
   Endpoint ep1_;
   Endpoint ep2_;
   RemoteIceParameterSource remote_ice_parameter_source_ = FROM_CANDIDATE;
@@ -1179,8 +1180,9 @@
         AddAddress(endpoint, kPrivateAddrs[endpoint]);
         // Add a single NAT of the desired type
         nat()
-            ->AddTranslator(kPublicAddrs[endpoint], kNatAddrs[endpoint],
-                            static_cast<rtc::NATType>(config - NAT_FULL_CONE))
+            ->AddTranslator(
+                kPublicAddrs[endpoint], kNatAddrs[endpoint],
+                static_cast<webrtc::NATType>(config - NAT_FULL_CONE))
             ->AddClient(kPrivateAddrs[endpoint]);
         break;
       case NAT_DOUBLE_CONE:
@@ -1189,10 +1191,10 @@
         // Add a two cascaded NATs of the desired types
         nat()
             ->AddTranslator(kPublicAddrs[endpoint], kNatAddrs[endpoint],
-                            (config == NAT_DOUBLE_CONE) ? rtc::NAT_OPEN_CONE
-                                                        : rtc::NAT_SYMMETRIC)
+                            (config == NAT_DOUBLE_CONE) ? webrtc::NAT_OPEN_CONE
+                                                        : webrtc::NAT_SYMMETRIC)
             ->AddTranslator(kPrivateAddrs[endpoint],
-                            kCascadedNatAddrs[endpoint], rtc::NAT_OPEN_CONE)
+                            kCascadedNatAddrs[endpoint], webrtc::NAT_OPEN_CONE)
             ->AddClient(kCascadedPrivateAddrs[endpoint]);
         break;
       case BLOCK_UDP:
@@ -2639,14 +2641,14 @@
     RTC_CHECK_GE(nat_type, NAT_FULL_CONE);
     RTC_CHECK_LE(nat_type, NAT_SYMMETRIC);
     CreatePortAllocators(env);
-    rtc::NATSocketServer::Translator* outer_nat = nat()->AddTranslator(
+    webrtc::NATSocketServer::Translator* outer_nat = nat()->AddTranslator(
         kPublicAddrs[0], kNatAddrs[0],
-        static_cast<rtc::NATType>(nat_type - NAT_FULL_CONE));
+        static_cast<webrtc::NATType>(nat_type - NAT_FULL_CONE));
     ConfigureEndpoint(outer_nat, 0, config1);
     ConfigureEndpoint(outer_nat, 1, config2);
     set_remote_ice_parameter_source(FROM_SETICEPARAMETERS);
   }
-  void ConfigureEndpoint(rtc::NATSocketServer::Translator* nat,
+  void ConfigureEndpoint(webrtc::NATSocketServer::Translator* nat,
                          int endpoint,
                          Config config) {
     RTC_CHECK(config <= NAT_SYMMETRIC);
@@ -2656,7 +2658,7 @@
     } else {
       AddAddress(endpoint, kCascadedPrivateAddrs[endpoint]);
       nat->AddTranslator(kPrivateAddrs[endpoint], kCascadedNatAddrs[endpoint],
-                         static_cast<rtc::NATType>(config - NAT_FULL_CONE))
+                         static_cast<webrtc::NATType>(config - NAT_FULL_CONE))
           ->AddClient(kCascadedPrivateAddrs[endpoint]);
     }
   }
@@ -5755,7 +5757,7 @@
     return *channel_;
   }
 
-  TestTurnServer* turn_server() { return &turn_server_; }
+  webrtc::TestTurnServer* turn_server() { return &turn_server_; }
 
   // This verifies the next pingable connection has the expected candidates'
   // types and, for relay local candidate, the expected relay protocol and ping
@@ -5776,7 +5778,7 @@
  private:
   std::unique_ptr<BasicPortAllocator> port_allocator_;
   rtc::FakeNetworkManager network_manager_;
-  TestTurnServer turn_server_;
+  webrtc::TestTurnServer turn_server_;
   std::unique_ptr<P2PTransportChannel> channel_;
 };
 
@@ -7172,7 +7174,7 @@
       rtc::CreateDefaultSocketServer();
   rtc::AutoSocketServerThread main_thread(socket_server.get());
   rtc::BasicPacketSocketFactory packet_socket_factory(socket_server.get());
-  MockIceControllerFactory factory;
+  webrtc::MockIceControllerFactory factory;
   FakePortAllocator pa(rtc::Thread::Current(), &packet_socket_factory,
                        &env.field_trials());
   EXPECT_CALL(factory, RecordIceControllerCreated()).Times(1);
@@ -7191,7 +7193,7 @@
       rtc::CreateDefaultSocketServer();
   rtc::AutoSocketServerThread main_thread(socket_server.get());
   rtc::BasicPacketSocketFactory packet_socket_factory(socket_server.get());
-  MockActiveIceControllerFactory factory;
+  webrtc::MockActiveIceControllerFactory factory;
   FakePortAllocator pa(rtc::Thread::Current(), &packet_socket_factory,
                        &env.field_trials());
   EXPECT_CALL(factory, RecordActiveIceControllerCreated()).Times(1);
diff --git a/p2p/base/packet_transport_internal_unittest.cc b/p2p/base/packet_transport_internal_unittest.cc
index d4428de..7886c74 100644
--- a/p2p/base/packet_transport_internal_unittest.cc
+++ b/p2p/base/packet_transport_internal_unittest.cc
@@ -22,7 +22,7 @@
 
 TEST(PacketTransportInternal,
      NotifyPacketReceivedPassthrougPacketToRegisteredListener) {
-  rtc::FakePacketTransport packet_transport("test");
+  webrtc::FakePacketTransport packet_transport("test");
   MockFunction<void(rtc::PacketTransportInternal*, const rtc::ReceivedPacket&)>
       receiver;
 
@@ -42,7 +42,7 @@
 }
 
 TEST(PacketTransportInternal, NotifiesOnceOnClose) {
-  rtc::FakePacketTransport packet_transport("test");
+  webrtc::FakePacketTransport packet_transport("test");
   int call_count = 0;
   packet_transport.SetOnCloseCallback([&]() { ++call_count; });
   ASSERT_EQ(call_count, 0);
diff --git a/p2p/base/port_unittest.cc b/p2p/base/port_unittest.cc
index eb3a4c7..1e2bf99 100644
--- a/p2p/base/port_unittest.cc
+++ b/p2p/base/port_unittest.cc
@@ -81,11 +81,6 @@
 using rtc::AsyncPacketSocket;
 using rtc::ByteBufferReader;
 using rtc::ByteBufferWriter;
-using rtc::NAT_ADDR_RESTRICTED;
-using rtc::NAT_OPEN_CONE;
-using rtc::NAT_PORT_RESTRICTED;
-using rtc::NAT_SYMMETRIC;
-using rtc::NATType;
 using rtc::PacketSocketFactory;
 using rtc::Socket;
 using ::testing::Eq;
@@ -93,6 +88,11 @@
 using ::testing::IsTrue;
 using ::testing::NotNull;
 using webrtc::IceCandidateType;
+using ::webrtc::NAT_ADDR_RESTRICTED;
+using ::webrtc::NAT_OPEN_CONE;
+using ::webrtc::NAT_PORT_RESTRICTED;
+using ::webrtc::NAT_SYMMETRIC;
+using ::webrtc::NATType;
 using ::webrtc::SocketAddress;
 
 namespace cricket {
@@ -104,10 +104,10 @@
 const SocketAddress kLocalAddr1("192.168.1.2", 0);
 const SocketAddress kLocalAddr2("192.168.1.3", 0);
 const SocketAddress kLinkLocalIPv6Addr("fe80::aabb:ccff:fedd:eeff", 0);
-const SocketAddress kNatAddr1("77.77.77.77", rtc::NAT_SERVER_UDP_PORT);
-const SocketAddress kNatAddr2("88.88.88.88", rtc::NAT_SERVER_UDP_PORT);
-const SocketAddress kStunAddr("99.99.99.1", STUN_SERVER_PORT);
-const SocketAddress kTurnUdpIntAddr("99.99.99.4", STUN_SERVER_PORT);
+const SocketAddress kNatAddr1("77.77.77.77", webrtc::NAT_SERVER_UDP_PORT);
+const SocketAddress kNatAddr2("88.88.88.88", webrtc::NAT_SERVER_UDP_PORT);
+const SocketAddress kStunAddr("99.99.99.1", webrtc::STUN_SERVER_PORT);
+const SocketAddress kTurnUdpIntAddr("99.99.99.4", webrtc::STUN_SERVER_PORT);
 const SocketAddress kTurnTcpIntAddr("99.99.99.4", 5010);
 const SocketAddress kTurnUdpExtAddr("99.99.99.5", 0);
 const RelayCredentials kRelayCredentials("test", "test");
@@ -434,7 +434,8 @@
         nat_factory2_(ss_.get(), kNatAddr2, SocketAddress()),
         nat_socket_factory1_(&nat_factory1_),
         nat_socket_factory2_(&nat_factory2_),
-        stun_server_(TestStunServer::Create(ss_.get(), kStunAddr, main_)),
+        stun_server_(
+            webrtc::TestStunServer::Create(ss_.get(), kStunAddr, main_)),
         turn_server_(&main_, ss_.get(), kTurnUdpIntAddr, kTurnUdpExtAddr),
         username_(rtc::CreateRandomString(ICE_UFRAG_LENGTH)),
         password_(rtc::CreateRandomString(ICE_PWD_LENGTH)),
@@ -466,8 +467,8 @@
     auto port2 = CreateStunPort(kLocalAddr2, &nat_socket_factory2_);
     port2->SetIceRole(cricket::ICEROLE_CONTROLLED);
     TestConnectivity("udp", std::move(port1), StunName(ntype), std::move(port2),
-                     ntype == NAT_OPEN_CONE, true, ntype != NAT_SYMMETRIC,
-                     true);
+                     ntype == webrtc::NAT_OPEN_CONE, true,
+                     ntype != webrtc::NAT_SYMMETRIC, true);
   }
   void TestLocalToRelay(webrtc::ProtocolType proto) {
     auto port1 = CreateUdpPort(kLocalAddr1);
@@ -484,7 +485,7 @@
     auto port2 = CreateUdpPort(kLocalAddr2);
     port2->SetIceRole(cricket::ICEROLE_CONTROLLED);
     TestConnectivity(StunName(ntype), std::move(port1), "udp", std::move(port2),
-                     true, ntype != NAT_SYMMETRIC, true, true);
+                     true, ntype != webrtc::NAT_SYMMETRIC, true, true);
   }
   void TestStunToStun(NATType ntype1, NATType ntype2) {
     nat_server1_ = CreateNatServer(kNatAddr1, ntype1);
@@ -494,9 +495,11 @@
     auto port2 = CreateStunPort(kLocalAddr2, &nat_socket_factory2_);
     port2->SetIceRole(cricket::ICEROLE_CONTROLLED);
     TestConnectivity(StunName(ntype1), std::move(port1), StunName(ntype2),
-                     std::move(port2), ntype2 == NAT_OPEN_CONE,
-                     ntype1 != NAT_SYMMETRIC, ntype2 != NAT_SYMMETRIC,
-                     ntype1 + ntype2 < (NAT_PORT_RESTRICTED + NAT_SYMMETRIC));
+                     std::move(port2), ntype2 == webrtc::NAT_OPEN_CONE,
+                     ntype1 != webrtc::NAT_SYMMETRIC,
+                     ntype2 != webrtc::NAT_SYMMETRIC,
+                     ntype1 + ntype2 <
+                         (webrtc::NAT_PORT_RESTRICTED + webrtc::NAT_SYMMETRIC));
   }
   void TestStunToRelay(NATType ntype, webrtc::ProtocolType proto) {
     nat_server1_ = CreateNatServer(kNatAddr1, ntype);
@@ -505,8 +508,8 @@
     auto port2 = CreateRelayPort(kLocalAddr2, proto, webrtc::PROTO_UDP);
     port2->SetIceRole(cricket::ICEROLE_CONTROLLED);
     TestConnectivity(StunName(ntype), std::move(port1), RelayName(proto),
-                     std::move(port2), false, ntype != NAT_SYMMETRIC, true,
-                     true);
+                     std::move(port2), false, ntype != webrtc::NAT_SYMMETRIC,
+                     true, true);
   }
   void TestTcpToTcp() {
     auto port1 = CreateTcpPort(kLocalAddr1);
@@ -649,20 +652,20 @@
     return port;
   }
 
-  std::unique_ptr<rtc::NATServer> CreateNatServer(const SocketAddress& addr,
-                                                  rtc::NATType type) {
-    return std::make_unique<rtc::NATServer>(type, main_, ss_.get(), addr, addr,
-                                            main_, ss_.get(), addr);
+  std::unique_ptr<webrtc::NATServer> CreateNatServer(const SocketAddress& addr,
+                                                     webrtc::NATType type) {
+    return std::make_unique<webrtc::NATServer>(type, main_, ss_.get(), addr,
+                                               addr, main_, ss_.get(), addr);
   }
   static const char* StunName(NATType type) {
     switch (type) {
-      case NAT_OPEN_CONE:
+      case webrtc::NAT_OPEN_CONE:
         return "stun(open cone)";
-      case NAT_ADDR_RESTRICTED:
+      case webrtc::NAT_ADDR_RESTRICTED:
         return "stun(addr restricted)";
-      case NAT_PORT_RESTRICTED:
+      case webrtc::NAT_PORT_RESTRICTED:
         return "stun(port restricted)";
-      case NAT_SYMMETRIC:
+      case webrtc::NAT_SYMMETRIC:
         return "stun(symmetric)";
       default:
         return "stun(?)";
@@ -944,14 +947,14 @@
   std::unique_ptr<rtc::VirtualSocketServer> ss_;
   rtc::AutoSocketServerThread main_;
   rtc::BasicPacketSocketFactory socket_factory_;
-  std::unique_ptr<rtc::NATServer> nat_server1_;
-  std::unique_ptr<rtc::NATServer> nat_server2_;
-  rtc::NATSocketFactory nat_factory1_;
-  rtc::NATSocketFactory nat_factory2_;
+  std::unique_ptr<webrtc::NATServer> nat_server1_;
+  std::unique_ptr<webrtc::NATServer> nat_server2_;
+  webrtc::NATSocketFactory nat_factory1_;
+  webrtc::NATSocketFactory nat_factory2_;
   rtc::BasicPacketSocketFactory nat_socket_factory1_;
   rtc::BasicPacketSocketFactory nat_socket_factory2_;
-  TestStunServer::StunServerPtr stun_server_;
-  TestTurnServer turn_server_;
+  webrtc::TestStunServer::StunServerPtr stun_server_;
+  webrtc::TestTurnServer turn_server_;
   std::string username_;
   std::string password_;
   bool role_conflict_;
@@ -1263,19 +1266,19 @@
 }
 
 TEST_F(PortTest, TestLocalToConeNat) {
-  TestLocalToStun(NAT_OPEN_CONE);
+  TestLocalToStun(webrtc::NAT_OPEN_CONE);
 }
 
 TEST_F(PortTest, TestLocalToARNat) {
-  TestLocalToStun(NAT_ADDR_RESTRICTED);
+  TestLocalToStun(webrtc::NAT_ADDR_RESTRICTED);
 }
 
 TEST_F(PortTest, TestLocalToPRNat) {
-  TestLocalToStun(NAT_PORT_RESTRICTED);
+  TestLocalToStun(webrtc::NAT_PORT_RESTRICTED);
 }
 
 TEST_F(PortTest, TestLocalToSymNat) {
-  TestLocalToStun(NAT_SYMMETRIC);
+  TestLocalToStun(webrtc::NAT_SYMMETRIC);
 }
 
 // Flaky: https://code.google.com/p/webrtc/issues/detail?id=3316.
@@ -1285,105 +1288,105 @@
 
 // Cone NAT -> XXXX
 TEST_F(PortTest, TestConeNatToLocal) {
-  TestStunToLocal(NAT_OPEN_CONE);
+  TestStunToLocal(webrtc::NAT_OPEN_CONE);
 }
 
 TEST_F(PortTest, TestConeNatToConeNat) {
-  TestStunToStun(NAT_OPEN_CONE, NAT_OPEN_CONE);
+  TestStunToStun(webrtc::NAT_OPEN_CONE, webrtc::NAT_OPEN_CONE);
 }
 
 TEST_F(PortTest, TestConeNatToARNat) {
-  TestStunToStun(NAT_OPEN_CONE, NAT_ADDR_RESTRICTED);
+  TestStunToStun(webrtc::NAT_OPEN_CONE, webrtc::NAT_ADDR_RESTRICTED);
 }
 
 TEST_F(PortTest, TestConeNatToPRNat) {
-  TestStunToStun(NAT_OPEN_CONE, NAT_PORT_RESTRICTED);
+  TestStunToStun(webrtc::NAT_OPEN_CONE, webrtc::NAT_PORT_RESTRICTED);
 }
 
 TEST_F(PortTest, TestConeNatToSymNat) {
-  TestStunToStun(NAT_OPEN_CONE, NAT_SYMMETRIC);
+  TestStunToStun(webrtc::NAT_OPEN_CONE, webrtc::NAT_SYMMETRIC);
 }
 
 TEST_F(PortTest, TestConeNatToTurn) {
-  TestStunToRelay(NAT_OPEN_CONE, webrtc::PROTO_UDP);
+  TestStunToRelay(webrtc::NAT_OPEN_CONE, webrtc::PROTO_UDP);
 }
 
 // Address-restricted NAT -> XXXX
 TEST_F(PortTest, TestARNatToLocal) {
-  TestStunToLocal(NAT_ADDR_RESTRICTED);
+  TestStunToLocal(webrtc::NAT_ADDR_RESTRICTED);
 }
 
 TEST_F(PortTest, TestARNatToConeNat) {
-  TestStunToStun(NAT_ADDR_RESTRICTED, NAT_OPEN_CONE);
+  TestStunToStun(webrtc::NAT_ADDR_RESTRICTED, webrtc::NAT_OPEN_CONE);
 }
 
 TEST_F(PortTest, TestARNatToARNat) {
-  TestStunToStun(NAT_ADDR_RESTRICTED, NAT_ADDR_RESTRICTED);
+  TestStunToStun(webrtc::NAT_ADDR_RESTRICTED, webrtc::NAT_ADDR_RESTRICTED);
 }
 
 TEST_F(PortTest, TestARNatToPRNat) {
-  TestStunToStun(NAT_ADDR_RESTRICTED, NAT_PORT_RESTRICTED);
+  TestStunToStun(webrtc::NAT_ADDR_RESTRICTED, webrtc::NAT_PORT_RESTRICTED);
 }
 
 TEST_F(PortTest, TestARNatToSymNat) {
-  TestStunToStun(NAT_ADDR_RESTRICTED, NAT_SYMMETRIC);
+  TestStunToStun(webrtc::NAT_ADDR_RESTRICTED, webrtc::NAT_SYMMETRIC);
 }
 
 TEST_F(PortTest, TestARNatToTurn) {
-  TestStunToRelay(NAT_ADDR_RESTRICTED, webrtc::PROTO_UDP);
+  TestStunToRelay(webrtc::NAT_ADDR_RESTRICTED, webrtc::PROTO_UDP);
 }
 
 // Port-restricted NAT -> XXXX
 TEST_F(PortTest, TestPRNatToLocal) {
-  TestStunToLocal(NAT_PORT_RESTRICTED);
+  TestStunToLocal(webrtc::NAT_PORT_RESTRICTED);
 }
 
 TEST_F(PortTest, TestPRNatToConeNat) {
-  TestStunToStun(NAT_PORT_RESTRICTED, NAT_OPEN_CONE);
+  TestStunToStun(webrtc::NAT_PORT_RESTRICTED, webrtc::NAT_OPEN_CONE);
 }
 
 TEST_F(PortTest, TestPRNatToARNat) {
-  TestStunToStun(NAT_PORT_RESTRICTED, NAT_ADDR_RESTRICTED);
+  TestStunToStun(webrtc::NAT_PORT_RESTRICTED, webrtc::NAT_ADDR_RESTRICTED);
 }
 
 TEST_F(PortTest, TestPRNatToPRNat) {
-  TestStunToStun(NAT_PORT_RESTRICTED, NAT_PORT_RESTRICTED);
+  TestStunToStun(webrtc::NAT_PORT_RESTRICTED, webrtc::NAT_PORT_RESTRICTED);
 }
 
 TEST_F(PortTest, TestPRNatToSymNat) {
   // Will "fail"
-  TestStunToStun(NAT_PORT_RESTRICTED, NAT_SYMMETRIC);
+  TestStunToStun(webrtc::NAT_PORT_RESTRICTED, webrtc::NAT_SYMMETRIC);
 }
 
 TEST_F(PortTest, TestPRNatToTurn) {
-  TestStunToRelay(NAT_PORT_RESTRICTED, webrtc::PROTO_UDP);
+  TestStunToRelay(webrtc::NAT_PORT_RESTRICTED, webrtc::PROTO_UDP);
 }
 
 // Symmetric NAT -> XXXX
 TEST_F(PortTest, TestSymNatToLocal) {
-  TestStunToLocal(NAT_SYMMETRIC);
+  TestStunToLocal(webrtc::NAT_SYMMETRIC);
 }
 
 TEST_F(PortTest, TestSymNatToConeNat) {
-  TestStunToStun(NAT_SYMMETRIC, NAT_OPEN_CONE);
+  TestStunToStun(webrtc::NAT_SYMMETRIC, webrtc::NAT_OPEN_CONE);
 }
 
 TEST_F(PortTest, TestSymNatToARNat) {
-  TestStunToStun(NAT_SYMMETRIC, NAT_ADDR_RESTRICTED);
+  TestStunToStun(webrtc::NAT_SYMMETRIC, webrtc::NAT_ADDR_RESTRICTED);
 }
 
 TEST_F(PortTest, TestSymNatToPRNat) {
   // Will "fail"
-  TestStunToStun(NAT_SYMMETRIC, NAT_PORT_RESTRICTED);
+  TestStunToStun(webrtc::NAT_SYMMETRIC, webrtc::NAT_PORT_RESTRICTED);
 }
 
 TEST_F(PortTest, TestSymNatToSymNat) {
   // Will "fail"
-  TestStunToStun(NAT_SYMMETRIC, NAT_SYMMETRIC);
+  TestStunToStun(webrtc::NAT_SYMMETRIC, webrtc::NAT_SYMMETRIC);
 }
 
 TEST_F(PortTest, TestSymNatToTurn) {
-  TestStunToRelay(NAT_SYMMETRIC, webrtc::PROTO_UDP);
+  TestStunToRelay(webrtc::NAT_SYMMETRIC, webrtc::PROTO_UDP);
 }
 
 // Outbound TCP -> XXXX
@@ -2920,8 +2923,8 @@
 
 // This test verifies the foundation of different types of ICE candidates.
 TEST_F(PortTest, TestCandidateFoundation) {
-  std::unique_ptr<rtc::NATServer> nat_server(
-      CreateNatServer(kNatAddr1, NAT_OPEN_CONE));
+  std::unique_ptr<webrtc::NATServer> nat_server(
+      CreateNatServer(kNatAddr1, webrtc::NAT_OPEN_CONE));
   auto udpport1 = CreateUdpPort(kLocalAddr1);
   udpport1->PrepareAddress();
   auto udpport2 = CreateUdpPort(kLocalAddr1);
@@ -2973,10 +2976,10 @@
             turnport2->Candidates()[0].foundation());
 
   // Running a second turn server, to get different base IP address.
-  SocketAddress kTurnUdpIntAddr2("99.99.98.4", STUN_SERVER_PORT);
+  SocketAddress kTurnUdpIntAddr2("99.99.98.4", webrtc::STUN_SERVER_PORT);
   SocketAddress kTurnUdpExtAddr2("99.99.98.5", 0);
-  TestTurnServer turn_server2(rtc::Thread::Current(), vss(), kTurnUdpIntAddr2,
-                              kTurnUdpExtAddr2);
+  webrtc::TestTurnServer turn_server2(rtc::Thread::Current(), vss(),
+                                      kTurnUdpIntAddr2, kTurnUdpExtAddr2);
   auto turnport3 =
       CreateTurnPort(kLocalAddr1, nat_socket_factory1(), webrtc::PROTO_UDP,
                      webrtc::PROTO_UDP, kTurnUdpIntAddr2);
@@ -2990,8 +2993,9 @@
 
   // Start a TCP turn server, and check that two turn candidates have
   // different foundations if their relay protocols are different.
-  TestTurnServer turn_server3(rtc::Thread::Current(), vss(), kTurnTcpIntAddr,
-                              kTurnUdpExtAddr, webrtc::PROTO_TCP);
+  webrtc::TestTurnServer turn_server3(rtc::Thread::Current(), vss(),
+                                      kTurnTcpIntAddr, kTurnUdpExtAddr,
+                                      webrtc::PROTO_TCP);
   auto turnport4 = CreateTurnPort(kLocalAddr1, nat_socket_factory1(),
                                   webrtc::PROTO_TCP, webrtc::PROTO_UDP);
   turnport4->PrepareAddress();
@@ -3006,7 +3010,7 @@
 // This test verifies the related addresses of different types of
 // ICE candidates.
 TEST_F(PortTest, TestCandidateRelatedAddress) {
-  auto nat_server = CreateNatServer(kNatAddr1, NAT_OPEN_CONE);
+  auto nat_server = CreateNatServer(kNatAddr1, webrtc::NAT_OPEN_CONE);
   auto udpport = CreateUdpPort(kLocalAddr1);
   udpport->PrepareAddress();
   // For UDPPort, related address will be empty.
diff --git a/p2p/base/regathering_controller_unittest.cc b/p2p/base/regathering_controller_unittest.cc
index a396712..79773e7 100644
--- a/p2p/base/regathering_controller_unittest.cc
+++ b/p2p/base/regathering_controller_unittest.cc
@@ -33,10 +33,10 @@
                             cricket::PORTALLOCATOR_DISABLE_RELAY |
                             cricket::PORTALLOCATOR_DISABLE_TCP;
 // The address of the public STUN server.
-const webrtc::SocketAddress kStunAddr("99.99.99.1", cricket::STUN_SERVER_PORT);
+const webrtc::SocketAddress kStunAddr("99.99.99.1", webrtc::STUN_SERVER_PORT);
 // The addresses for the public TURN server.
 const webrtc::SocketAddress kTurnUdpIntAddr("99.99.99.3",
-                                            cricket::STUN_SERVER_PORT);
+                                            webrtc::STUN_SERVER_PORT);
 const cricket::RelayCredentials kRelayCredentials("test", "test");
 const char kIceUfrag[] = "UF00";
 const char kIcePwd[] = "TESTICEPWD00000000000000";
@@ -51,7 +51,7 @@
   RegatheringControllerTest()
       : vss_(std::make_unique<rtc::VirtualSocketServer>()),
         thread_(vss_.get()),
-        ice_transport_(std::make_unique<cricket::MockIceTransport>()),
+        ice_transport_(std::make_unique<MockIceTransport>()),
         packet_socket_factory_(
             std::make_unique<rtc::BasicPacketSocketFactory>(vss_.get())),
         allocator_(std::make_unique<cricket::FakePortAllocator>(
diff --git a/p2p/base/stun_port_unittest.cc b/p2p/base/stun_port_unittest.cc
index 66b2725..ee1662f 100644
--- a/p2p/base/stun_port_unittest.cc
+++ b/p2p/base/stun_port_unittest.cc
@@ -71,14 +71,14 @@
 static const SocketAddress kMsdnAddress("unittest-mdns-host-name.local", 0);
 static const SocketAddress kPublicIP("212.116.91.133", 0);
 static const SocketAddress kNatAddr(kPublicIP.ipaddr(),
-                                    rtc::NAT_SERVER_UDP_PORT);
+                                    webrtc::NAT_SERVER_UDP_PORT);
 static const SocketAddress kStunServerAddr1("34.38.54.120", 5000);
 static const SocketAddress kStunServerAddr2("34.38.54.120", 4000);
 
 static const SocketAddress kPrivateIPv6("2001:4860:4860::8844", 0);
 static const SocketAddress kPublicIPv6("2002:4860:4860::8844", 5000);
 static const SocketAddress kNatAddrIPv6(kPublicIPv6.ipaddr(),
-                                        rtc::NAT_SERVER_UDP_PORT);
+                                        webrtc::NAT_SERVER_UDP_PORT);
 static const SocketAddress kStunServerAddrIPv6Addr("2003:4860:4860::8844",
                                                    5000);
 
@@ -140,7 +140,7 @@
         nat_factory_(ss_.get(), nat_server_address, nat_server_address),
         nat_socket_factory_(&nat_factory_),
         mdns_responder_provider_(new FakeMdnsResponderProvider()),
-        nat_server_(CreateNatServer(nat_server_address, rtc::NAT_OPEN_CONE)),
+        nat_server_(CreateNatServer(nat_server_address, webrtc::NAT_OPEN_CONE)),
         done_(false),
         error_(false),
         stun_keepalive_delay_(1),
@@ -150,14 +150,14 @@
     for (const auto& addr : stun_server_addresses) {
       RTC_CHECK(addr.family() == address.family());
       stun_servers_.push_back(
-          cricket::TestStunServer::Create(ss_.get(), addr, thread_));
+          webrtc::TestStunServer::Create(ss_.get(), addr, thread_));
     }
   }
 
-  std::unique_ptr<rtc::NATServer> CreateNatServer(const SocketAddress& addr,
-                                                  rtc::NATType type) {
-    return std::make_unique<rtc::NATServer>(type, thread_, ss_.get(), addr,
-                                            addr, thread_, ss_.get(), addr);
+  std::unique_ptr<webrtc::NATServer> CreateNatServer(const SocketAddress& addr,
+                                                     webrtc::NATType type) {
+    return std::make_unique<webrtc::NATServer>(type, thread_, ss_.get(), addr,
+                                               addr, thread_, ss_.get(), addr);
   }
 
   virtual rtc::PacketSocketFactory* socket_factory() {
@@ -291,8 +291,8 @@
     return &networks_.back();
   }
 
-  cricket::TestStunServer* stun_server_1() { return stun_servers_[0].get(); }
-  cricket::TestStunServer* stun_server_2() { return stun_servers_[1].get(); }
+  webrtc::TestStunServer* stun_server_1() { return stun_servers_[0].get(); }
+  webrtc::TestStunServer* stun_server_2() { return stun_servers_[1].get(); }
 
   rtc::AutoSocketServerThread& thread() { return thread_; }
   rtc::SocketFactory* nat_factory() { return &nat_factory_; }
@@ -303,13 +303,13 @@
 
   std::unique_ptr<rtc::VirtualSocketServer> ss_;
   rtc::AutoSocketServerThread thread_;
-  rtc::NATSocketFactory nat_factory_;
+  webrtc::NATSocketFactory nat_factory_;
   rtc::BasicPacketSocketFactory nat_socket_factory_;
   std::unique_ptr<cricket::UDPPort> stun_port_;
-  std::vector<cricket::TestStunServer::StunServerPtr> stun_servers_;
+  std::vector<webrtc::TestStunServer::StunServerPtr> stun_servers_;
   std::unique_ptr<rtc::AsyncPacketSocket> socket_;
   std::unique_ptr<rtc::MdnsResponderProvider> mdns_responder_provider_;
-  std::unique_ptr<rtc::NATServer> nat_server_;
+  std::unique_ptr<webrtc::NATServer> nat_server_;
   bool done_;
   bool error_;
   int stun_keepalive_delay_;
@@ -406,12 +406,12 @@
   }
 
   void SetDnsResolverExpectations(
-      rtc::MockDnsResolvingPacketSocketFactory::Expectations expectations) {
+      webrtc::MockDnsResolvingPacketSocketFactory::Expectations expectations) {
     socket_factory_.SetExpectations(expectations);
   }
 
  private:
-  rtc::MockDnsResolvingPacketSocketFactory socket_factory_;
+  webrtc::MockDnsResolvingPacketSocketFactory socket_factory_;
 };
 
 // Test that we can get an address from a STUN server specified by a hostname.
@@ -861,12 +861,12 @@
   }
 
   void SetDnsResolverExpectations(
-      rtc::MockDnsResolvingPacketSocketFactory::Expectations expectations) {
+      webrtc::MockDnsResolvingPacketSocketFactory::Expectations expectations) {
     socket_factory_.SetExpectations(expectations);
   }
 
  private:
-  rtc::MockDnsResolvingPacketSocketFactory socket_factory_;
+  webrtc::MockDnsResolvingPacketSocketFactory socket_factory_;
 };
 
 // Test that we can get an address from a STUN server specified by a hostname.
diff --git a/p2p/base/turn_port_unittest.cc b/p2p/base/turn_port_unittest.cc
index 807e237..c9235e5 100644
--- a/p2p/base/turn_port_unittest.cc
+++ b/p2p/base/turn_port_unittest.cc
@@ -88,12 +88,12 @@
 static const SocketAddress kLocalIPv6Addr2("2401:fa00:4:2000:be30:5bff:fee5:d4",
                                            0);
 static const SocketAddress kTurnUdpIntAddr("99.99.99.3",
-                                           cricket::TURN_SERVER_PORT);
+                                           webrtc::TURN_SERVER_PORT);
 static const SocketAddress kTurnTcpIntAddr("99.99.99.4",
-                                           cricket::TURN_SERVER_PORT);
+                                           webrtc::TURN_SERVER_PORT);
 static const SocketAddress kTurnUdpExtAddr("99.99.99.5", 0);
 static const SocketAddress kTurnAlternateIntAddr("99.99.99.6",
-                                                 cricket::TURN_SERVER_PORT);
+                                                 webrtc::TURN_SERVER_PORT);
 // Port for redirecting to a TCP Web server. Should not work.
 static const SocketAddress kTurnDangerousAddr("99.99.99.7", 81);
 // Port 53 (the DNS port); should work.
@@ -103,14 +103,13 @@
 // Port 443 (the HTTPS port); should work.
 static const SocketAddress kTurnPort443Addr("99.99.99.7", 443);
 // The default TURN server port.
-static const SocketAddress kTurnIntAddr("99.99.99.7",
-                                        cricket::TURN_SERVER_PORT);
+static const SocketAddress kTurnIntAddr("99.99.99.7", webrtc::TURN_SERVER_PORT);
 static const SocketAddress kTurnIPv6IntAddr(
     "2400:4030:2:2c00:be30:abcd:efab:cdef",
-    cricket::TURN_SERVER_PORT);
+    webrtc::TURN_SERVER_PORT);
 static const SocketAddress kTurnUdpIPv6IntAddr(
     "2400:4030:1:2c00:be30:abcd:efab:cdef",
-    cricket::TURN_SERVER_PORT);
+    webrtc::TURN_SERVER_PORT);
 static const SocketAddress kTurnInvalidAddr("www.google.invalid.", 3478);
 static const SocketAddress kTurnValidAddr("www.google.valid.", 3478);
 
@@ -512,7 +511,7 @@
     std::vector<webrtc::SocketAddress> redirect_addresses;
     redirect_addresses.push_back(kTurnAlternateIntAddr);
 
-    TestTurnRedirector redirector(redirect_addresses);
+    webrtc::TestTurnRedirector redirector(redirect_addresses);
 
     turn_server_.AddInternalSocket(kTurnIntAddr, protocol_type);
     turn_server_.AddInternalSocket(kTurnAlternateIntAddr, protocol_type);
@@ -544,7 +543,7 @@
     std::vector<webrtc::SocketAddress> redirect_addresses;
     redirect_addresses.push_back(kTurnIPv6IntAddr);
 
-    TestTurnRedirector redirector(redirect_addresses);
+    webrtc::TestTurnRedirector redirector(redirect_addresses);
     turn_server_.AddInternalSocket(kTurnIntAddr, protocol_type);
     turn_server_.set_redirect_hook(&redirector);
     CreateTurnPort(kTurnUsername, kTurnPassword,
@@ -565,7 +564,7 @@
     redirect_addresses.push_back(kTurnAlternateIntAddr);
     redirect_addresses.push_back(kTurnIntAddr);
 
-    TestTurnRedirector redirector(redirect_addresses);
+    webrtc::TestTurnRedirector redirector(redirect_addresses);
 
     turn_server_.AddInternalSocket(kTurnIntAddr, protocol_type);
     turn_server_.AddInternalSocket(kTurnAlternateIntAddr, protocol_type);
@@ -593,7 +592,7 @@
     redirect_addresses.push_back(kTurnAlternateIntAddr);
     redirect_addresses.push_back(kTurnAlternateIntAddr);
 
-    TestTurnRedirector redirector(redirect_addresses);
+    webrtc::TestTurnRedirector redirector(redirect_addresses);
 
     turn_server_.AddInternalSocket(kTurnIntAddr, protocol_type);
     turn_server_.AddInternalSocket(kTurnAlternateIntAddr, protocol_type);
@@ -625,7 +624,7 @@
     // Pick an unusual address in the 127.0.0.0/8 range to make sure more than
     // 127.0.0.1 is covered.
     SocketAddress loopback_address(ipv6 ? "::1" : "127.1.2.3",
-                                   TURN_SERVER_PORT);
+                                   webrtc::TURN_SERVER_PORT);
     redirect_addresses.push_back(loopback_address);
 
     // Make a socket and bind it to the local port, to make extra sure no
@@ -639,7 +638,7 @@
       ASSERT_EQ(0, loopback_socket->Listen(1));
     }
 
-    TestTurnRedirector redirector(redirect_addresses);
+    webrtc::TestTurnRedirector redirector(redirect_addresses);
 
     turn_server_.AddInternalSocket(server_address, protocol_type);
     turn_server_.set_redirect_hook(&redirector);
@@ -954,7 +953,7 @@
   std::unique_ptr<TurnPortTestVirtualSocketServer> ss_;
   rtc::AutoSocketServerThread main_;
   std::unique_ptr<rtc::AsyncPacketSocket> socket_;
-  TestTurnServer turn_server_;
+  webrtc::TestTurnServer turn_server_;
   std::unique_ptr<TurnPort> turn_port_;
   std::unique_ptr<UDPPort> udp_port_;
   bool turn_ready_ = false;
@@ -1036,7 +1035,7 @@
   TestTurnAllocateSucceeds(kSimulatedRtt * 2);
 }
 
-class TurnLoggingIdValidator : public StunMessageObserver {
+class TurnLoggingIdValidator : public webrtc::StunMessageObserver {
  public:
   explicit TurnLoggingIdValidator(const char* expect_val)
       : expect_val_(expect_val) {}
@@ -1999,7 +1998,7 @@
 }
 #endif
 
-class MessageObserver : public StunMessageObserver {
+class MessageObserver : public webrtc::StunMessageObserver {
  public:
   MessageObserver(unsigned int* message_counter,
                   unsigned int* channel_data_counter,
@@ -2014,7 +2013,7 @@
     }
     // Implementation defined attributes are returned as ByteString
     const StunByteStringAttribute* attr =
-        msg->GetByteString(TestTurnCustomizer::STUN_ATTR_COUNTER);
+        msg->GetByteString(webrtc::TestTurnCustomizer::STUN_ATTR_COUNTER);
     if (attr != nullptr && attr_counter_ != nullptr) {
       rtc::ByteBufferReader buf(attr->array_view());
       unsigned int val = ~0u;
@@ -2045,7 +2044,7 @@
   unsigned int observer_message_counter = 0;
   unsigned int observer_channel_data_counter = 0;
   unsigned int observer_attr_counter = 0;
-  TestTurnCustomizer* customizer = new TestTurnCustomizer();
+  webrtc::TestTurnCustomizer* customizer = new webrtc::TestTurnCustomizer();
   std::unique_ptr<MessageObserver> validator(new MessageObserver(
       &observer_message_counter, &observer_channel_data_counter,
       &observer_attr_counter));
@@ -2075,7 +2074,7 @@
   unsigned int observer_message_counter = 0;
   unsigned int observer_channel_data_counter = 0;
   unsigned int observer_attr_counter = 0;
-  TestTurnCustomizer* customizer = new TestTurnCustomizer();
+  webrtc::TestTurnCustomizer* customizer = new webrtc::TestTurnCustomizer();
   std::unique_ptr<MessageObserver> validator(new MessageObserver(
       &observer_message_counter, &observer_channel_data_counter,
       &observer_attr_counter));
@@ -2104,7 +2103,7 @@
   unsigned int observer_message_counter = 0;
   unsigned int observer_channel_data_counter = 0;
   unsigned int observer_attr_counter = 0;
-  TestTurnCustomizer* customizer = new TestTurnCustomizer();
+  webrtc::TestTurnCustomizer* customizer = new webrtc::TestTurnCustomizer();
   std::unique_ptr<MessageObserver> validator(new MessageObserver(
       &observer_message_counter, &observer_channel_data_counter,
       &observer_attr_counter));
@@ -2170,7 +2169,7 @@
   std::vector<webrtc::SocketAddress> redirect_addresses;
   redirect_addresses.push_back(kTurnDangerousAddr);
 
-  TestTurnRedirector redirector(redirect_addresses);
+  webrtc::TestTurnRedirector redirector(redirect_addresses);
 
   turn_server_.AddInternalSocket(kTurnIntAddr, protocol_type);
   turn_server_.AddInternalSocket(kTurnDangerousAddr, protocol_type);
@@ -2205,12 +2204,12 @@
   }
 
   void SetDnsResolverExpectations(
-      rtc::MockDnsResolvingPacketSocketFactory::Expectations expectations) {
+      webrtc::MockDnsResolvingPacketSocketFactory::Expectations expectations) {
     socket_factory_.SetExpectations(expectations);
   }
 
  private:
-  rtc::MockDnsResolvingPacketSocketFactory socket_factory_;
+  webrtc::MockDnsResolvingPacketSocketFactory socket_factory_;
 };
 
 // Test an allocation from a TURN server specified by a hostname.
diff --git a/p2p/base/wrapping_active_ice_controller_unittest.cc b/p2p/base/wrapping_active_ice_controller_unittest.cc
index 1f2f399..433e4c3 100644
--- a/p2p/base/wrapping_active_ice_controller_unittest.cc
+++ b/p2p/base/wrapping_active_ice_controller_unittest.cc
@@ -30,11 +30,11 @@
 using ::cricket::IceMode;
 using ::cricket::IceRecheckEvent;
 using ::cricket::IceSwitchReason;
-using ::cricket::MockIceAgent;
-using ::cricket::MockIceController;
-using ::cricket::MockIceControllerFactory;
 using ::cricket::NominationMode;
 using ::cricket::WrappingActiveIceController;
+using ::webrtc::MockIceAgent;
+using ::webrtc::MockIceController;
+using ::webrtc::MockIceControllerFactory;
 
 using ::testing::_;
 using ::testing::ElementsAreArray;
diff --git a/p2p/client/basic_port_allocator_unittest.cc b/p2p/client/basic_port_allocator_unittest.cc
index 31355d3..1a08137 100644
--- a/p2p/client/basic_port_allocator_unittest.cc
+++ b/p2p/client/basic_port_allocator_unittest.cc
@@ -93,10 +93,12 @@
 static const SocketAddress kClientIPv6Addr5(
     "2401:fa00:4:5000:be30:5bff:fee5:c3",
     0);
-static const SocketAddress kNatUdpAddr("77.77.77.77", rtc::NAT_SERVER_UDP_PORT);
-static const SocketAddress kNatTcpAddr("77.77.77.77", rtc::NAT_SERVER_TCP_PORT);
+static const SocketAddress kNatUdpAddr("77.77.77.77",
+                                       webrtc::NAT_SERVER_UDP_PORT);
+static const SocketAddress kNatTcpAddr("77.77.77.77",
+                                       webrtc::NAT_SERVER_TCP_PORT);
 static const SocketAddress kRemoteClientAddr("22.22.22.22", 0);
-static const SocketAddress kStunAddr("99.99.99.1", cricket::STUN_SERVER_PORT);
+static const SocketAddress kStunAddr("99.99.99.1", webrtc::STUN_SERVER_PORT);
 static const SocketAddress kTurnUdpIntAddr("99.99.99.4", 3478);
 static const SocketAddress kTurnUdpIntIPv6Addr(
     "2402:fb00:4:1000:be30:5bff:fee5:c3",
@@ -159,7 +161,8 @@
         // must be called.
         nat_factory_(vss_.get(), kNatUdpAddr, kNatTcpAddr),
         nat_socket_factory_(new rtc::BasicPacketSocketFactory(&nat_factory_)),
-        stun_server_(TestStunServer::Create(fss_.get(), kStunAddr, thread_)),
+        stun_server_(
+            webrtc::TestStunServer::Create(fss_.get(), kStunAddr, thread_)),
         turn_server_(rtc::Thread::Current(),
                      fss_.get(),
                      kTurnUdpIntAddr,
@@ -477,7 +480,7 @@
   void ResetWithStunServer(const webrtc::SocketAddress& stun_server,
                            bool with_nat) {
     if (with_nat) {
-      nat_server_.reset(new rtc::NATServer(
+      nat_server_.reset(new webrtc::NATServer(
           rtc::NAT_OPEN_CONE, thread_, vss_.get(), kNatUdpAddr, kNatTcpAddr,
           thread_, vss_.get(), webrtc::SocketAddress(kNatUdpAddr.ipaddr(), 0)));
     } else {
@@ -504,11 +507,11 @@
   std::unique_ptr<rtc::FirewallSocketServer> fss_;
   rtc::BasicPacketSocketFactory socket_factory_;
   rtc::AutoSocketServerThread thread_;
-  std::unique_ptr<rtc::NATServer> nat_server_;
-  rtc::NATSocketFactory nat_factory_;
+  std::unique_ptr<webrtc::NATServer> nat_server_;
+  webrtc::NATSocketFactory nat_factory_;
   std::unique_ptr<rtc::BasicPacketSocketFactory> nat_socket_factory_;
-  TestStunServer::StunServerPtr stun_server_;
-  TestTurnServer turn_server_;
+  webrtc::TestStunServer::StunServerPtr stun_server_;
+  webrtc::TestTurnServer turn_server_;
   rtc::FakeNetworkManager network_manager_;
   std::unique_ptr<BasicPortAllocator> allocator_;
   std::unique_ptr<PortAllocatorSession> session_;
diff --git a/p2p/stunprober/stun_prober_unittest.cc b/p2p/stunprober/stun_prober_unittest.cc
index 2d778e8..eff4e22 100644
--- a/p2p/stunprober/stun_prober_unittest.cc
+++ b/p2p/stunprober/stun_prober_unittest.cc
@@ -51,9 +51,9 @@
         main_(ss_.get()),
         result_(StunProber::SUCCESS),
         stun_server_1_(
-            cricket::TestStunServer::Create(ss_.get(), kStunAddr1, main_)),
+            webrtc::TestStunServer::Create(ss_.get(), kStunAddr1, main_)),
         stun_server_2_(
-            cricket::TestStunServer::Create(ss_.get(), kStunAddr2, main_)) {
+            webrtc::TestStunServer::Create(ss_.get(), kStunAddr2, main_)) {
     stun_server_1_->set_fake_stun_addr(kStunMappedAddr);
     stun_server_2_->set_fake_stun_addr(kStunMappedAddr);
     rtc::InitializeSSL();
@@ -145,8 +145,8 @@
   std::unique_ptr<StunProber> prober_;
   int result_ = 0;
   bool stopped_ = false;
-  cricket::TestStunServer::StunServerPtr stun_server_1_;
-  cricket::TestStunServer::StunServerPtr stun_server_2_;
+  webrtc::TestStunServer::StunServerPtr stun_server_1_;
+  webrtc::TestStunServer::StunServerPtr stun_server_2_;
   StunProber::Stats stats_;
 };
 
diff --git a/p2p/test/fake_packet_transport.h b/p2p/test/fake_packet_transport.h
index b9162ee..86640b8 100644
--- a/p2p/test/fake_packet_transport.h
+++ b/p2p/test/fake_packet_transport.h
@@ -18,10 +18,10 @@
 #include "rtc_base/copy_on_write_buffer.h"
 #include "rtc_base/time_utils.h"
 
-namespace rtc {
+namespace webrtc {
 
 // Used to simulate a packet-based transport.
-class FakePacketTransport : public PacketTransportInternal {
+class FakePacketTransport : public rtc::PacketTransportInternal {
  public:
   explicit FakePacketTransport(const std::string& transport_name)
       : transport_name_(transport_name) {}
@@ -59,7 +59,7 @@
   bool receiving() const override { return receiving_; }
   int SendPacket(const char* data,
                  size_t len,
-                 const PacketOptions& options,
+                 const rtc::PacketOptions& options,
                  int /* flags */) override {
     if (!dest_ || error_ != 0) {
       return -1;
@@ -67,17 +67,17 @@
     CopyOnWriteBuffer packet(data, len);
     SendPacketInternal(packet, options);
 
-    SentPacket sent_packet(options.packet_id, TimeMillis());
+    rtc::SentPacket sent_packet(options.packet_id, rtc::TimeMillis());
     SignalSentPacket(this, sent_packet);
     return static_cast<int>(len);
   }
 
-  int SetOption(Socket::Option opt, int value) override {
+  int SetOption(rtc::Socket::Option opt, int value) override {
     options_[opt] = value;
     return 0;
   }
 
-  bool GetOption(Socket::Option opt, int* value) override {
+  bool GetOption(rtc::Socket::Option opt, int* value) override {
     auto it = options_.find(opt);
     if (it == options_.end()) {
       return false;
@@ -91,16 +91,16 @@
 
   const CopyOnWriteBuffer* last_sent_packet() { return &last_sent_packet_; }
 
-  std::optional<NetworkRoute> network_route() const override {
+  std::optional<rtc::NetworkRoute> network_route() const override {
     return network_route_;
   }
-  void SetNetworkRoute(std::optional<NetworkRoute> network_route) {
+  void SetNetworkRoute(std::optional<rtc::NetworkRoute> network_route) {
     network_route_ = network_route;
     SignalNetworkRouteChanged(network_route);
   }
 
-  using PacketTransportInternal::NotifyOnClose;
-  using PacketTransportInternal::NotifyPacketReceived;
+  using rtc::PacketTransportInternal::NotifyOnClose;
+  using rtc::PacketTransportInternal::NotifyPacketReceived;
 
  private:
   void set_writable(bool writable) {
@@ -127,8 +127,7 @@
     last_sent_packet_ = packet;
     if (dest_) {
       dest_->NotifyPacketReceived(rtc::ReceivedPacket(
-          packet, webrtc::SocketAddress(),
-          webrtc::Timestamp::Micros(rtc::TimeMicros()),
+          packet, SocketAddress(), Timestamp::Micros(rtc::TimeMicros()),
           options.ecn_1 ? EcnMarking::kEct1 : EcnMarking::kNotEct));
     }
   }
@@ -139,12 +138,18 @@
   bool writable_ = false;
   bool receiving_ = false;
 
-  std::map<Socket::Option, int> options_;
+  std::map<rtc::Socket::Option, int> options_;
   int error_ = 0;
 
-  std::optional<NetworkRoute> network_route_;
+  std::optional<rtc::NetworkRoute> network_route_;
 };
 
+}  //  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::FakePacketTransport;
 }  // namespace rtc
 
 #endif  // P2P_TEST_FAKE_PACKET_TRANSPORT_H_
diff --git a/p2p/test/mock_active_ice_controller.h b/p2p/test/mock_active_ice_controller.h
index 010bb9c..794c451 100644
--- a/p2p/test/mock_active_ice_controller.h
+++ b/p2p/test/mock_active_ice_controller.h
@@ -17,7 +17,7 @@
 #include "p2p/base/active_ice_controller_interface.h"
 #include "test/gmock.h"
 
-namespace cricket {
+namespace webrtc {
 
 class MockActiveIceController : public cricket::ActiveIceControllerInterface {
  public:
@@ -84,6 +84,13 @@
   MOCK_METHOD(void, RecordActiveIceControllerCreated, ());
 };
 
+}  //  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::MockActiveIceController;
+using ::webrtc::MockActiveIceControllerFactory;
 }  // namespace cricket
 
 #endif  // P2P_TEST_MOCK_ACTIVE_ICE_CONTROLLER_H_
diff --git a/p2p/test/mock_dns_resolving_packet_socket_factory.h b/p2p/test/mock_dns_resolving_packet_socket_factory.h
index ae3943b..f87f4cb 100644
--- a/p2p/test/mock_dns_resolving_packet_socket_factory.h
+++ b/p2p/test/mock_dns_resolving_packet_socket_factory.h
@@ -17,22 +17,23 @@
 #include "api/test/mock_async_dns_resolver.h"
 #include "p2p/base/basic_packet_socket_factory.h"
 
-namespace rtc {
+namespace webrtc {
 
 // A PacketSocketFactory implementation for tests that uses a mock DnsResolver
 // and allows setting expectations on the resolver and results.
-class MockDnsResolvingPacketSocketFactory : public BasicPacketSocketFactory {
+class MockDnsResolvingPacketSocketFactory
+    : public rtc::BasicPacketSocketFactory {
  public:
-  using Expectations = std::function<void(webrtc::MockAsyncDnsResolver*,
-                                          webrtc::MockAsyncDnsResolverResult*)>;
+  using Expectations =
+      std::function<void(MockAsyncDnsResolver*, MockAsyncDnsResolverResult*)>;
 
-  explicit MockDnsResolvingPacketSocketFactory(SocketFactory* socket_factory)
-      : BasicPacketSocketFactory(socket_factory) {}
+  explicit MockDnsResolvingPacketSocketFactory(
+      rtc::SocketFactory* socket_factory)
+      : rtc::BasicPacketSocketFactory(socket_factory) {}
 
-  std::unique_ptr<webrtc::AsyncDnsResolverInterface> CreateAsyncDnsResolver()
-      override {
-    std::unique_ptr<webrtc::MockAsyncDnsResolver> resolver =
-        std::make_unique<webrtc::MockAsyncDnsResolver>();
+  std::unique_ptr<AsyncDnsResolverInterface> CreateAsyncDnsResolver() override {
+    std::unique_ptr<MockAsyncDnsResolver> resolver =
+        std::make_unique<MockAsyncDnsResolver>();
     if (expectations_) {
       expectations_(resolver.get(), &resolver_result_);
     }
@@ -44,10 +45,16 @@
   }
 
  private:
-  webrtc::MockAsyncDnsResolverResult resolver_result_;
+  MockAsyncDnsResolverResult resolver_result_;
   Expectations expectations_;
 };
 
+}  //  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::MockDnsResolvingPacketSocketFactory;
 }  // namespace rtc
 
 #endif  // P2P_TEST_MOCK_DNS_RESOLVING_PACKET_SOCKET_FACTORY_H_
diff --git a/p2p/test/mock_ice_agent.h b/p2p/test/mock_ice_agent.h
index 7d25756..cd0fa93 100644
--- a/p2p/test/mock_ice_agent.h
+++ b/p2p/test/mock_ice_agent.h
@@ -19,32 +19,38 @@
 #include "p2p/base/transport_description.h"
 #include "test/gmock.h"
 
-namespace cricket {
+namespace webrtc {
 
-class MockIceAgent : public IceAgentInterface {
+class MockIceAgent : public cricket::IceAgentInterface {
  public:
   ~MockIceAgent() override = default;
 
   MOCK_METHOD(int64_t, GetLastPingSentMs, (), (override, const));
-  MOCK_METHOD(IceRole, GetIceRole, (), (override, const));
+  MOCK_METHOD(cricket::IceRole, GetIceRole, (), (override, const));
   MOCK_METHOD(void, OnStartedPinging, (), (override));
   MOCK_METHOD(void, UpdateConnectionStates, (), (override));
   MOCK_METHOD(void, UpdateState, (), (override));
   MOCK_METHOD(void,
               ForgetLearnedStateForConnections,
-              (rtc::ArrayView<const Connection* const>),
+              (rtc::ArrayView<const cricket::Connection* const>),
               (override));
-  MOCK_METHOD(void, SendPingRequest, (const Connection*), (override));
+  MOCK_METHOD(void, SendPingRequest, (const cricket::Connection*), (override));
   MOCK_METHOD(void,
               SwitchSelectedConnection,
-              (const Connection*, IceSwitchReason),
+              (const cricket::Connection*, cricket::IceSwitchReason),
               (override));
   MOCK_METHOD(bool,
               PruneConnections,
-              (rtc::ArrayView<const Connection* const>),
+              (rtc::ArrayView<const cricket::Connection* const>),
               (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::MockIceAgent;
 }  // namespace cricket
 
 #endif  // P2P_TEST_MOCK_ICE_AGENT_H_
diff --git a/p2p/test/mock_ice_controller.h b/p2p/test/mock_ice_controller.h
index d437786..ee812cd 100644
--- a/p2p/test/mock_ice_controller.h
+++ b/p2p/test/mock_ice_controller.h
@@ -18,7 +18,7 @@
 #include "p2p/base/ice_controller_interface.h"
 #include "test/gmock.h"
 
-namespace cricket {
+namespace webrtc {
 
 class MockIceController : public cricket::IceControllerInterface {
  public:
@@ -90,6 +90,13 @@
   MOCK_METHOD(void, RecordIceControllerCreated, ());
 };
 
+}  //  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::MockIceController;
+using ::webrtc::MockIceControllerFactory;
 }  // namespace cricket
 
 #endif  // P2P_TEST_MOCK_ICE_CONTROLLER_H_
diff --git a/p2p/test/mock_ice_transport.h b/p2p/test/mock_ice_transport.h
index 547f2c2..c3e32e5 100644
--- a/p2p/test/mock_ice_transport.h
+++ b/p2p/test/mock_ice_transport.h
@@ -18,10 +18,10 @@
 #include "p2p/base/ice_transport_internal.h"
 #include "test/gmock.h"
 
-namespace cricket {
+namespace webrtc {
 
 // Used in Chromium/remoting/protocol/channel_socket_adapter_unittest.cc
-class MockIceTransport : public IceTransportInternal {
+class MockIceTransport : public cricket::IceTransportInternal {
  public:
   MockIceTransport() {
     SignalReadyToSend(this);
@@ -43,34 +43,42 @@
               (cricket::IceTransportStats * ice_transport_stats),
               (override));
 
-  IceTransportState GetState() const override {
-    return IceTransportState::STATE_INIT;
+  cricket::IceTransportState GetState() const override {
+    return cricket::IceTransportState::STATE_INIT;
   }
-  webrtc::IceTransportState GetIceTransportState() const override {
-    return webrtc::IceTransportState::kNew;
+  IceTransportState GetIceTransportState() const override {
+    return IceTransportState::kNew;
   }
 
   const std::string& transport_name() const override { return transport_name_; }
   int component() const override { return 0; }
-  void SetIceRole(IceRole /* role */) override {}
+  void SetIceRole(cricket::IceRole /* role */) override {}
   // The ufrag and pwd in `ice_params` must be set
   // before candidate gathering can start.
-  void SetIceParameters(const IceParameters& /* ice_params */) override {}
-  void SetRemoteIceParameters(const IceParameters& /* ice_params */) override {}
-  void SetRemoteIceMode(IceMode /* mode */) override {}
-  void SetIceConfig(const IceConfig& config) override { ice_config_ = config; }
-  const IceConfig& config() const override { return ice_config_; }
+  void SetIceParameters(
+      const cricket::IceParameters& /* ice_params */) override {}
+  void SetRemoteIceParameters(
+      const cricket::IceParameters& /* ice_params */) override {}
+  void SetRemoteIceMode(cricket::IceMode /* mode */) override {}
+  void SetIceConfig(const cricket::IceConfig& config) override {
+    ice_config_ = config;
+  }
+  const cricket::IceConfig& config() const override { return ice_config_; }
   std::optional<int> GetRttEstimate() override { return std::nullopt; }
-  const Connection* selected_connection() const override { return nullptr; }
-  std::optional<const CandidatePair> GetSelectedCandidatePair() const override {
+  const cricket::Connection* selected_connection() const override {
+    return nullptr;
+  }
+  std::optional<const cricket::CandidatePair> GetSelectedCandidatePair()
+      const override {
     return std::nullopt;
   }
   void MaybeStartGathering() override {}
-  void AddRemoteCandidate(const Candidate& /* candidate */) override {}
-  void RemoveRemoteCandidate(const Candidate& /* candidate */) override {}
+  void AddRemoteCandidate(const cricket::Candidate& /* candidate */) override {}
+  void RemoveRemoteCandidate(
+      const cricket::Candidate& /* candidate */) override {}
   void RemoveAllRemoteCandidates() override {}
-  IceGatheringState gathering_state() const override {
-    return IceGatheringState::kIceGatheringComplete;
+  cricket::IceGatheringState gathering_state() const override {
+    return cricket::IceGatheringState::kIceGatheringComplete;
   }
 
   bool receiving() const override { return true; }
@@ -78,9 +86,15 @@
 
  private:
   std::string transport_name_;
-  IceConfig ice_config_;
+  cricket::IceConfig ice_config_;
 };
 
+}  //  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::MockIceTransport;
 }  // namespace cricket
 
 #endif  // P2P_TEST_MOCK_ICE_TRANSPORT_H_
diff --git a/p2p/test/nat_server.cc b/p2p/test/nat_server.cc
index c9e6f87..5513a5d 100644
--- a/p2p/test/nat_server.cc
+++ b/p2p/test/nat_server.cc
@@ -22,19 +22,19 @@
 #include "rtc_base/socket_adapters.h"
 #include "rtc_base/socket_address.h"
 
-namespace rtc {
+namespace webrtc {
 
 RouteCmp::RouteCmp(NAT* nat) : symmetric(nat->IsSymmetric()) {}
 
-size_t RouteCmp::operator()(const webrtc::SocketAddressPair& r) const {
+size_t RouteCmp::operator()(const SocketAddressPair& r) const {
   size_t h = r.source().Hash();
   if (symmetric)
     h ^= r.destination().Hash();
   return h;
 }
 
-bool RouteCmp::operator()(const webrtc::SocketAddressPair& r1,
-                          const webrtc::SocketAddressPair& r2) const {
+bool RouteCmp::operator()(const SocketAddressPair& r1,
+                          const SocketAddressPair& r2) const {
   if (r1.source() < r2.source())
     return true;
   if (r2.source() < r1.source())
@@ -49,7 +49,7 @@
 AddrCmp::AddrCmp(NAT* nat)
     : use_ip(nat->FiltersIP()), use_port(nat->FiltersPort()) {}
 
-size_t AddrCmp::operator()(const webrtc::SocketAddress& a) const {
+size_t AddrCmp::operator()(const SocketAddress& a) const {
   size_t h = 0;
   if (use_ip)
     h ^= webrtc::HashIP(a.ipaddr());
@@ -58,8 +58,8 @@
   return h;
 }
 
-bool AddrCmp::operator()(const webrtc::SocketAddress& a1,
-                         const webrtc::SocketAddress& a2) const {
+bool AddrCmp::operator()(const SocketAddress& a1,
+                         const SocketAddress& a2) const {
   if (use_ip && (a1.ipaddr() < a2.ipaddr()))
     return true;
   if (use_ip && (a2.ipaddr() < a1.ipaddr()))
@@ -73,16 +73,17 @@
 
 // Proxy socket that will capture the external destination address intended for
 // a TCP connection to the NAT server.
-class NATProxyServerSocket : public AsyncProxyServerSocket {
+class NATProxyServerSocket : public rtc::AsyncProxyServerSocket {
  public:
-  explicit NATProxyServerSocket(Socket* socket)
-      : AsyncProxyServerSocket(socket, kNATEncodedIPv6AddressSize) {
+  explicit NATProxyServerSocket(rtc::Socket* socket)
+      : rtc::AsyncProxyServerSocket(socket,
+                                    webrtc::kNATEncodedIPv6AddressSize) {
     BufferInput(true);
   }
 
-  void SendConnectResult(int err, const webrtc::SocketAddress& addr) override {
+  void SendConnectResult(int err, const SocketAddress& addr) override {
     char code = err ? 1 : 0;
-    BufferedReadAdapter::DirectSend(&code, sizeof(char));
+    rtc::BufferedReadAdapter::DirectSend(&code, sizeof(char));
   }
 
  protected:
@@ -93,13 +94,13 @@
 
     int family = data[1];
     RTC_DCHECK(family == AF_INET || family == AF_INET6);
-    if ((family == AF_INET && *len < kNATEncodedIPv4AddressSize) ||
-        (family == AF_INET6 && *len < kNATEncodedIPv6AddressSize)) {
+    if ((family == AF_INET && *len < webrtc::kNATEncodedIPv4AddressSize) ||
+        (family == AF_INET6 && *len < webrtc::kNATEncodedIPv6AddressSize)) {
       return;
     }
 
-    webrtc::SocketAddress dest_addr;
-    size_t address_length = UnpackAddressFromNAT(
+    SocketAddress dest_addr;
+    size_t address_length = webrtc::UnpackAddressFromNAT(
         MakeArrayView(reinterpret_cast<const uint8_t*>(data), *len),
         &dest_addr);
     *len -= address_length;
@@ -116,28 +117,28 @@
   }
 };
 
-class NATProxyServer : public ProxyServer {
+class NATProxyServer : public rtc::ProxyServer {
  public:
-  NATProxyServer(SocketFactory* int_factory,
-                 const webrtc::SocketAddress& int_addr,
-                 SocketFactory* ext_factory,
-                 const webrtc::SocketAddress& ext_ip)
-      : ProxyServer(int_factory, int_addr, ext_factory, ext_ip) {}
+  NATProxyServer(rtc::SocketFactory* int_factory,
+                 const SocketAddress& int_addr,
+                 rtc::SocketFactory* ext_factory,
+                 const SocketAddress& ext_ip)
+      : rtc::ProxyServer(int_factory, int_addr, ext_factory, ext_ip) {}
 
  protected:
-  AsyncProxyServerSocket* WrapSocket(Socket* socket) override {
+  rtc::AsyncProxyServerSocket* WrapSocket(rtc::Socket* socket) override {
     return new NATProxyServerSocket(socket);
   }
 };
 
 NATServer::NATServer(NATType type,
                      rtc::Thread& internal_socket_thread,
-                     SocketFactory* internal,
-                     const webrtc::SocketAddress& internal_udp_addr,
-                     const webrtc::SocketAddress& internal_tcp_addr,
+                     rtc::SocketFactory* internal,
+                     const SocketAddress& internal_udp_addr,
+                     const SocketAddress& internal_tcp_addr,
                      rtc::Thread& external_socket_thread,
-                     SocketFactory* external,
-                     const webrtc::SocketAddress& external_ip)
+                     rtc::SocketFactory* external,
+                     const SocketAddress& external_ip)
     : internal_socket_thread_(internal_socket_thread),
       external_socket_thread_(external_socket_thread),
       external_(external),
@@ -145,7 +146,8 @@
   nat_ = NAT::Create(type);
 
   internal_socket_thread_.BlockingCall([&] {
-    udp_server_socket_ = AsyncUDPSocket::Create(internal, internal_udp_addr);
+    udp_server_socket_ =
+        rtc::AsyncUDPSocket::Create(internal, internal_udp_addr);
     udp_server_socket_->RegisterReceivedPacketCallback(
         [&](rtc::AsyncPacketSocket* socket, const rtc::ReceivedPacket& packet) {
           OnInternalUDPPacket(socket, packet);
@@ -171,15 +173,15 @@
   delete ext_map_;
 }
 
-void NATServer::OnInternalUDPPacket(AsyncPacketSocket* socket,
+void NATServer::OnInternalUDPPacket(rtc::AsyncPacketSocket* socket,
                                     const rtc::ReceivedPacket& packet) {
   RTC_DCHECK(internal_socket_thread_.IsCurrent());
   // Read the intended destination from the wire.
-  webrtc::SocketAddress dest_addr;
-  size_t length = UnpackAddressFromNAT(packet.payload(), &dest_addr);
+  SocketAddress dest_addr;
+  size_t length = webrtc::UnpackAddressFromNAT(packet.payload(), &dest_addr);
 
   // Find the translation for these addresses (allocating one if necessary).
-  webrtc::SocketAddressPair route(packet.source_address(), dest_addr);
+  SocketAddressPair route(packet.source_address(), dest_addr);
   InternalMap::iterator iter = int_map_->find(route);
   if (iter == int_map_->end()) {
     Translate(route);
@@ -197,10 +199,10 @@
   iter->second->socket->SendTo(buf + length, size - length, dest_addr, options);
 }
 
-void NATServer::OnExternalUDPPacket(AsyncPacketSocket* socket,
+void NATServer::OnExternalUDPPacket(rtc::AsyncPacketSocket* socket,
                                     const rtc::ReceivedPacket& packet) {
   RTC_DCHECK(external_socket_thread_.IsCurrent());
-  webrtc::SocketAddress local_addr = socket->GetLocalAddress();
+  SocketAddress local_addr = socket->GetLocalAddress();
 
   // Find the translation for this addresses.
   ExternalMap::iterator iter = ext_map_->find(local_addr);
@@ -217,9 +219,10 @@
   // Forward this packet to the internal address.
   // First prepend the address in a quasi-STUN format.
   std::unique_ptr<char[]> real_buf(
-      new char[packet.payload().size() + kNATEncodedIPv6AddressSize]);
-  size_t addrlength = PackAddressForNAT(
-      real_buf.get(), packet.payload().size() + kNATEncodedIPv6AddressSize,
+      new char[packet.payload().size() + webrtc::kNATEncodedIPv6AddressSize]);
+  size_t addrlength = webrtc::PackAddressForNAT(
+      real_buf.get(),
+      packet.payload().size() + webrtc::kNATEncodedIPv6AddressSize,
       packet.source_address());
   // Copy the data part after the address.
   rtc::PacketOptions options;
@@ -230,9 +233,10 @@
                              iter->second->route.source(), options);
 }
 
-void NATServer::Translate(const webrtc::SocketAddressPair& route) {
+void NATServer::Translate(const SocketAddressPair& route) {
   external_socket_thread_.BlockingCall([&] {
-    AsyncUDPSocket* socket = AsyncUDPSocket::Create(external_, external_ip_);
+    rtc::AsyncUDPSocket* socket =
+        rtc::AsyncUDPSocket::Create(external_, external_ip_);
 
     if (!socket) {
       RTC_LOG(LS_ERROR) << "Couldn't find a free port!";
@@ -250,12 +254,12 @@
 }
 
 bool NATServer::ShouldFilterOut(TransEntry* entry,
-                                const webrtc::SocketAddress& ext_addr) {
+                                const SocketAddress& ext_addr) {
   return entry->AllowlistContains(ext_addr);
 }
 
-NATServer::TransEntry::TransEntry(const webrtc::SocketAddressPair& r,
-                                  AsyncUDPSocket* s,
+NATServer::TransEntry::TransEntry(const SocketAddressPair& r,
+                                  rtc::AsyncUDPSocket* s,
                                   NAT* nat)
     : route(r), socket(s) {
   allowlist = new AddressSet(AddrCmp(nat));
@@ -266,15 +270,14 @@
   delete socket;
 }
 
-void NATServer::TransEntry::AllowlistInsert(const webrtc::SocketAddress& addr) {
-  webrtc::MutexLock lock(&mutex_);
+void NATServer::TransEntry::AllowlistInsert(const SocketAddress& addr) {
+  MutexLock lock(&mutex_);
   allowlist->insert(addr);
 }
 
-bool NATServer::TransEntry::AllowlistContains(
-    const webrtc::SocketAddress& ext_addr) {
-  webrtc::MutexLock lock(&mutex_);
+bool NATServer::TransEntry::AllowlistContains(const SocketAddress& ext_addr) {
+  MutexLock lock(&mutex_);
   return allowlist->find(ext_addr) == allowlist->end();
 }
 
-}  // namespace rtc
+}  // namespace webrtc
diff --git a/p2p/test/nat_server.h b/p2p/test/nat_server.h
index ecdd70a..7ae038c 100644
--- a/p2p/test/nat_server.h
+++ b/p2p/test/nat_server.h
@@ -22,16 +22,16 @@
 #include "rtc_base/synchronization/mutex.h"
 #include "rtc_base/thread.h"
 
-namespace rtc {
+namespace webrtc {
 
 // Change how routes (socketaddress pairs) are compared based on the type of
 // NAT.  The NAT server maintains a hashtable of the routes that it knows
 // about.  So these affect which routes are treated the same.
 struct RouteCmp {
   explicit RouteCmp(NAT* nat);
-  size_t operator()(const webrtc::SocketAddressPair& r) const;
-  bool operator()(const webrtc::SocketAddressPair& r1,
-                  const webrtc::SocketAddressPair& r2) const;
+  size_t operator()(const SocketAddressPair& r) const;
+  bool operator()(const SocketAddressPair& r1,
+                  const SocketAddressPair& r2) const;
 
   bool symmetric;
 };
@@ -39,9 +39,8 @@
 // Changes how addresses are compared based on the filtering rules of the NAT.
 struct AddrCmp {
   explicit AddrCmp(NAT* nat);
-  size_t operator()(const webrtc::SocketAddress& r) const;
-  bool operator()(const webrtc::SocketAddress& r1,
-                  const webrtc::SocketAddress& r2) const;
+  size_t operator()(const SocketAddress& r) const;
+  bool operator()(const SocketAddress& r1, const SocketAddress& r2) const;
 
   bool use_ip;
   bool use_port;
@@ -63,70 +62,78 @@
  public:
   NATServer(NATType type,
             rtc::Thread& internal_socket_thread,
-            SocketFactory* internal,
-            const webrtc::SocketAddress& internal_udp_addr,
-            const webrtc::SocketAddress& internal_tcp_addr,
+            rtc::SocketFactory* internal,
+            const SocketAddress& internal_udp_addr,
+            const SocketAddress& internal_tcp_addr,
             rtc::Thread& external_socket_thread,
-            SocketFactory* external,
-            const webrtc::SocketAddress& external_ip);
+            rtc::SocketFactory* external,
+            const SocketAddress& external_ip);
   ~NATServer();
 
   NATServer(const NATServer&) = delete;
   NATServer& operator=(const NATServer&) = delete;
 
-  webrtc::SocketAddress internal_udp_address() const {
+  SocketAddress internal_udp_address() const {
     return udp_server_socket_->GetLocalAddress();
   }
 
-  webrtc::SocketAddress internal_tcp_address() const {
+  SocketAddress internal_tcp_address() const {
     return tcp_proxy_server_->GetServerAddress();
   }
 
   // Packets received on one of the networks.
-  void OnInternalUDPPacket(AsyncPacketSocket* socket,
+  void OnInternalUDPPacket(rtc::AsyncPacketSocket* socket,
                            const rtc::ReceivedPacket& packet);
-  void OnExternalUDPPacket(AsyncPacketSocket* socket,
+  void OnExternalUDPPacket(rtc::AsyncPacketSocket* socket,
                            const rtc::ReceivedPacket& packet);
 
  private:
-  typedef std::set<webrtc::SocketAddress, AddrCmp> AddressSet;
+  typedef std::set<SocketAddress, AddrCmp> AddressSet;
 
   /* Records a translation and the associated external socket. */
   struct TransEntry {
-    TransEntry(const webrtc::SocketAddressPair& r, AsyncUDPSocket* s, NAT* nat);
+    TransEntry(const SocketAddressPair& r, rtc::AsyncUDPSocket* s, NAT* nat);
     ~TransEntry();
 
-    void AllowlistInsert(const webrtc::SocketAddress& addr);
-    bool AllowlistContains(const webrtc::SocketAddress& ext_addr);
+    void AllowlistInsert(const SocketAddress& addr);
+    bool AllowlistContains(const SocketAddress& ext_addr);
 
-    webrtc::SocketAddressPair route;
-    AsyncUDPSocket* socket;
+    SocketAddressPair route;
+    rtc::AsyncUDPSocket* socket;
     AddressSet* allowlist;
-    webrtc::Mutex mutex_;
+    Mutex mutex_;
   };
 
-  typedef std::map<webrtc::SocketAddressPair, TransEntry*, RouteCmp>
-      InternalMap;
-  typedef std::map<webrtc::SocketAddress, TransEntry*> ExternalMap;
+  typedef std::map<SocketAddressPair, TransEntry*, RouteCmp> InternalMap;
+  typedef std::map<SocketAddress, TransEntry*> ExternalMap;
 
   /* Creates a new entry that translates the given route. */
-  void Translate(const webrtc::SocketAddressPair& route);
+  void Translate(const SocketAddressPair& route);
 
   /* Determines whether the NAT would filter out a packet from this address. */
-  bool ShouldFilterOut(TransEntry* entry,
-                       const webrtc::SocketAddress& ext_addr);
+  bool ShouldFilterOut(TransEntry* entry, const SocketAddress& ext_addr);
 
   NAT* nat_;
   rtc::Thread& internal_socket_thread_;
   rtc::Thread& external_socket_thread_;
-  SocketFactory* external_;
-  webrtc::SocketAddress external_ip_;
-  AsyncUDPSocket* udp_server_socket_;
-  ProxyServer* tcp_proxy_server_;
+  rtc::SocketFactory* external_;
+  SocketAddress external_ip_;
+  rtc::AsyncUDPSocket* udp_server_socket_;
+  rtc::ProxyServer* tcp_proxy_server_;
   InternalMap* int_map_;
   ExternalMap* ext_map_;
 };
 
+}  //  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::AddrCmp;
+using ::webrtc::NAT_SERVER_TCP_PORT;
+using ::webrtc::NAT_SERVER_UDP_PORT;
+using ::webrtc::NATServer;
+using ::webrtc::RouteCmp;
 }  // namespace rtc
 
 #endif  // P2P_TEST_NAT_SERVER_H_
diff --git a/p2p/test/nat_socket_factory.cc b/p2p/test/nat_socket_factory.cc
index 21f55ae..04bd045 100644
--- a/p2p/test/nat_socket_factory.cc
+++ b/p2p/test/nat_socket_factory.cc
@@ -18,15 +18,15 @@
 #include "rtc_base/logging.h"
 #include "rtc_base/virtual_socket_server.h"
 
-namespace rtc {
+namespace webrtc {
 
 // Packs the given socketaddress into the buffer in buf, in the quasi-STUN
 // format that the natserver uses.
 // Returns 0 if an invalid address is passed.
 size_t PackAddressForNAT(char* buf,
                          size_t buf_size,
-                         const webrtc::SocketAddress& remote_addr) {
-  const webrtc::IPAddress& ip = remote_addr.ipaddr();
+                         const SocketAddress& remote_addr) {
+  const IPAddress& ip = remote_addr.ipaddr();
   int family = ip.family();
   buf[0] = 0;
   buf[1] = family;
@@ -51,7 +51,7 @@
 // quasi-STUN format. Returns the length of the address (i.e., the offset into
 // data where the original packet starts).
 size_t UnpackAddressFromNAT(rtc::ArrayView<const uint8_t> buf,
-                            webrtc::SocketAddress* remote_addr) {
+                            SocketAddress* remote_addr) {
   RTC_CHECK(buf.size() >= 8);
   RTC_DCHECK(buf.data()[0] == 0);
   int family = buf[1];
@@ -59,19 +59,19 @@
       *(reinterpret_cast<const uint16_t*>(&buf.data()[2])));
   if (family == AF_INET) {
     const in_addr* v4addr = reinterpret_cast<const in_addr*>(&buf.data()[4]);
-    *remote_addr = webrtc::SocketAddress(webrtc::IPAddress(*v4addr), port);
+    *remote_addr = SocketAddress(IPAddress(*v4addr), port);
     return kNATEncodedIPv4AddressSize;
   } else if (family == AF_INET6) {
     RTC_DCHECK(buf.size() >= 20);
     const in6_addr* v6addr = reinterpret_cast<const in6_addr*>(&buf.data()[4]);
-    *remote_addr = webrtc::SocketAddress(webrtc::IPAddress(*v6addr), port);
+    *remote_addr = SocketAddress(IPAddress(*v6addr), port);
     return kNATEncodedIPv6AddressSize;
   }
   return 0U;
 }
 
 // NATSocket
-class NATSocket : public Socket, public sigslot::has_slots<> {
+class NATSocket : public rtc::Socket, public sigslot::has_slots<> {
  public:
   explicit NATSocket(NATInternalSocketFactory* sf, int family, int type)
       : sf_(sf),
@@ -82,15 +82,15 @@
 
   ~NATSocket() override { delete socket_; }
 
-  webrtc::SocketAddress GetLocalAddress() const override {
-    return (socket_) ? socket_->GetLocalAddress() : webrtc::SocketAddress();
+  SocketAddress GetLocalAddress() const override {
+    return (socket_) ? socket_->GetLocalAddress() : SocketAddress();
   }
 
-  webrtc::SocketAddress GetRemoteAddress() const override {
+  SocketAddress GetRemoteAddress() const override {
     return remote_addr_;  // will be NIL if not connected
   }
 
-  int Bind(const webrtc::SocketAddress& addr) override {
+  int Bind(const SocketAddress& addr) override {
     if (socket_) {  // already bound, bubble up error
       return -1;
     }
@@ -98,13 +98,12 @@
     return BindInternal(addr);
   }
 
-  int Connect(const webrtc::SocketAddress& addr) override {
+  int Connect(const SocketAddress& addr) override {
     int result = 0;
     // If we're not already bound (meaning `socket_` is null), bind to ANY
     // address.
     if (!socket_) {
-      result =
-          BindInternal(webrtc::SocketAddress(webrtc::GetAnyIP(family_), 0));
+      result = BindInternal(SocketAddress(webrtc::GetAnyIP(family_), 0));
       if (result < 0) {
         return result;
       }
@@ -130,7 +129,7 @@
 
   int SendTo(const void* data,
              size_t size,
-             const webrtc::SocketAddress& addr) override {
+             const SocketAddress& addr) override {
     RTC_DCHECK(!connected_ || addr == remote_addr_);
     if (server_addr_.IsNil() || type_ == SOCK_STREAM) {
       return socket_->SendTo(data, size, addr);
@@ -150,13 +149,13 @@
   }
 
   int Recv(void* data, size_t size, int64_t* timestamp) override {
-    webrtc::SocketAddress addr;
+    SocketAddress addr;
     return RecvFrom(data, size, &addr, timestamp);
   }
 
   int RecvFrom(void* data,
                size_t size,
-               webrtc::SocketAddress* out_addr,
+               SocketAddress* out_addr,
                int64_t* timestamp) override {
     if (server_addr_.IsNil() || type_ == SOCK_STREAM) {
       return socket_->RecvFrom(data, size, out_addr, timestamp);
@@ -166,16 +165,15 @@
     buf_.EnsureCapacity(size + kNATEncodedIPv6AddressSize);
 
     // Read the packet from the socket.
-    Socket::ReceiveBuffer receive_buffer(buf_);
+    rtc::Socket::ReceiveBuffer receive_buffer(buf_);
     int result = socket_->RecvFrom(receive_buffer);
     if (result >= 0) {
       RTC_DCHECK(receive_buffer.source_address == server_addr_);
       *timestamp =
-          receive_buffer.arrival_time.value_or(webrtc::Timestamp::Micros(0))
-              .us();
+          receive_buffer.arrival_time.value_or(Timestamp::Micros(0)).us();
 
       // Decode the wire packet into the actual results.
-      webrtc::SocketAddress real_remote_addr;
+      SocketAddress real_remote_addr;
       size_t addrlength = UnpackAddressFromNAT(buf_, &real_remote_addr);
       memcpy(data, buf_.data() + addrlength, result - addrlength);
 
@@ -200,7 +198,7 @@
       result = socket_->Close();
       if (result >= 0) {
         connected_ = false;
-        remote_addr_ = webrtc::SocketAddress();
+        remote_addr_ = SocketAddress();
         delete socket_;
         socket_ = nullptr;
       }
@@ -209,7 +207,7 @@
   }
 
   int Listen(int backlog) override { return socket_->Listen(backlog); }
-  Socket* Accept(webrtc::SocketAddress* paddr) override {
+  rtc::Socket* Accept(SocketAddress* paddr) override {
     return socket_->Accept(paddr);
   }
   int GetError() const override {
@@ -232,7 +230,7 @@
     return socket_ ? socket_->SetOption(opt, value) : -1;
   }
 
-  void OnConnectEvent(Socket* socket) {
+  void OnConnectEvent(rtc::Socket* socket) {
     // If we're NATed, we need to send a message with the real addr to use.
     RTC_DCHECK(socket == socket_);
     if (server_addr_.IsNil()) {
@@ -242,7 +240,7 @@
       SendConnectRequest();
     }
   }
-  void OnReadEvent(Socket* socket) {
+  void OnReadEvent(rtc::Socket* socket) {
     // If we're NATed, we need to process the connect reply.
     RTC_DCHECK(socket == socket_);
     if (type_ == SOCK_STREAM && !server_addr_.IsNil() && !connected_) {
@@ -251,17 +249,17 @@
       SignalReadEvent(this);
     }
   }
-  void OnWriteEvent(Socket* socket) {
+  void OnWriteEvent(rtc::Socket* socket) {
     RTC_DCHECK(socket == socket_);
     SignalWriteEvent(this);
   }
-  void OnCloseEvent(Socket* socket, int error) {
+  void OnCloseEvent(rtc::Socket* socket, int error) {
     RTC_DCHECK(socket == socket_);
     SignalCloseEvent(this, error);
   }
 
  private:
-  int BindInternal(const webrtc::SocketAddress& addr) {
+  int BindInternal(const SocketAddress& addr) {
     RTC_DCHECK(!socket_);
 
     int result;
@@ -305,31 +303,31 @@
   int family_;
   int type_;
   bool connected_;
-  webrtc::SocketAddress remote_addr_;
-  webrtc::SocketAddress server_addr_;  // address of the NAT server
-  Socket* socket_;
+  SocketAddress remote_addr_;
+  SocketAddress server_addr_;  // address of the NAT server
+  rtc::Socket* socket_;
   // Need to hold error in case it occurs before the socket is created.
   int error_ = 0;
   Buffer buf_;
 };
 
 // NATSocketFactory
-NATSocketFactory::NATSocketFactory(SocketFactory* factory,
-                                   const webrtc::SocketAddress& nat_udp_addr,
-                                   const webrtc::SocketAddress& nat_tcp_addr)
+NATSocketFactory::NATSocketFactory(rtc::SocketFactory* factory,
+                                   const SocketAddress& nat_udp_addr,
+                                   const SocketAddress& nat_tcp_addr)
     : factory_(factory),
       nat_udp_addr_(nat_udp_addr),
       nat_tcp_addr_(nat_tcp_addr) {}
 
-Socket* NATSocketFactory::CreateSocket(int family, int type) {
+rtc::Socket* NATSocketFactory::CreateSocket(int family, int type) {
   return new NATSocket(this, family, type);
 }
 
-Socket* NATSocketFactory::CreateInternalSocket(
+rtc::Socket* NATSocketFactory::CreateInternalSocket(
     int family,
     int type,
-    const webrtc::SocketAddress& local_addr,
-    webrtc::SocketAddress* nat_addr) {
+    const SocketAddress& local_addr,
+    SocketAddress* nat_addr) {
   if (type == SOCK_STREAM) {
     *nat_addr = nat_tcp_addr_;
   } else {
@@ -339,17 +337,17 @@
 }
 
 // NATSocketServer
-NATSocketServer::NATSocketServer(SocketServer* server)
+NATSocketServer::NATSocketServer(rtc::SocketServer* server)
     : server_(server), msg_queue_(nullptr) {}
 
 NATSocketServer::Translator* NATSocketServer::GetTranslator(
-    const webrtc::SocketAddress& ext_ip) {
+    const SocketAddress& ext_ip) {
   return nats_.Get(ext_ip);
 }
 
 NATSocketServer::Translator* NATSocketServer::AddTranslator(
-    const webrtc::SocketAddress& ext_ip,
-    const webrtc::SocketAddress& int_ip,
+    const SocketAddress& ext_ip,
+    const SocketAddress& int_ip,
     NATType type) {
   // Fail if a translator already exists with this extternal address.
   if (nats_.Get(ext_ip))
@@ -359,21 +357,20 @@
       ext_ip, new Translator(this, type, int_ip, *msg_queue_, server_, ext_ip));
 }
 
-void NATSocketServer::RemoveTranslator(const webrtc::SocketAddress& ext_ip) {
+void NATSocketServer::RemoveTranslator(const SocketAddress& ext_ip) {
   nats_.Remove(ext_ip);
 }
 
-Socket* NATSocketServer::CreateSocket(int family, int type) {
+rtc::Socket* NATSocketServer::CreateSocket(int family, int type) {
   return new NATSocket(this, family, type);
 }
 
-void NATSocketServer::SetMessageQueue(Thread* queue) {
+void NATSocketServer::SetMessageQueue(rtc::Thread* queue) {
   msg_queue_ = queue;
   server_->SetMessageQueue(queue);
 }
 
-bool NATSocketServer::Wait(webrtc::TimeDelta max_wait_duration,
-                           bool process_io) {
+bool NATSocketServer::Wait(TimeDelta max_wait_duration, bool process_io) {
   return server_->Wait(max_wait_duration, process_io);
 }
 
@@ -381,12 +378,12 @@
   server_->WakeUp();
 }
 
-Socket* NATSocketServer::CreateInternalSocket(
+rtc::Socket* NATSocketServer::CreateInternalSocket(
     int family,
     int type,
-    const webrtc::SocketAddress& local_addr,
-    webrtc::SocketAddress* nat_addr) {
-  Socket* socket = nullptr;
+    const SocketAddress& local_addr,
+    SocketAddress* nat_addr) {
+  rtc::Socket* socket = nullptr;
   Translator* nat = nats_.FindClient(local_addr);
   if (nat) {
     socket = nat->internal_factory()->CreateSocket(family, type);
@@ -401,15 +398,15 @@
 // NATSocketServer::Translator
 NATSocketServer::Translator::Translator(NATSocketServer* server,
                                         NATType type,
-                                        const webrtc::SocketAddress& int_ip,
-                                        Thread& external_socket_thread,
-                                        SocketFactory* ext_factory,
-                                        const webrtc::SocketAddress& ext_ip)
+                                        const SocketAddress& int_ip,
+                                        rtc::Thread& external_socket_thread,
+                                        rtc::SocketFactory* ext_factory,
+                                        const SocketAddress& ext_ip)
     : server_(server) {
   // Create a new private network, and a NATServer running on the private
   // network that bridges to the external network. Also tell the private
   // network to use the same message queue as us.
-  internal_server_ = std::make_unique<VirtualSocketServer>();
+  internal_server_ = std::make_unique<rtc::VirtualSocketServer>();
   internal_server_->SetMessageQueue(server_->queue());
   nat_server_ = std::make_unique<NATServer>(
       type, *server->queue(), internal_server_.get(), int_ip, int_ip,
@@ -421,13 +418,13 @@
 }
 
 NATSocketServer::Translator* NATSocketServer::Translator::GetTranslator(
-    const webrtc::SocketAddress& ext_ip) {
+    const SocketAddress& ext_ip) {
   return nats_.Get(ext_ip);
 }
 
 NATSocketServer::Translator* NATSocketServer::Translator::AddTranslator(
-    const webrtc::SocketAddress& ext_ip,
-    const webrtc::SocketAddress& int_ip,
+    const SocketAddress& ext_ip,
+    const SocketAddress& int_ip,
     NATType type) {
   // Fail if a translator already exists with this extternal address.
   if (nats_.Get(ext_ip))
@@ -438,13 +435,12 @@
                                           *server_->queue(), server_, ext_ip));
 }
 void NATSocketServer::Translator::RemoveTranslator(
-    const webrtc::SocketAddress& ext_ip) {
+    const SocketAddress& ext_ip) {
   nats_.Remove(ext_ip);
   RemoveClient(ext_ip);
 }
 
-bool NATSocketServer::Translator::AddClient(
-    const webrtc::SocketAddress& int_ip) {
+bool NATSocketServer::Translator::AddClient(const SocketAddress& int_ip) {
   // Fail if a client already exists with this internal address.
   if (clients_.find(int_ip) != clients_.end())
     return false;
@@ -453,16 +449,15 @@
   return true;
 }
 
-void NATSocketServer::Translator::RemoveClient(
-    const webrtc::SocketAddress& int_ip) {
-  std::set<webrtc::SocketAddress>::iterator it = clients_.find(int_ip);
+void NATSocketServer::Translator::RemoveClient(const SocketAddress& int_ip) {
+  std::set<SocketAddress>::iterator it = clients_.find(int_ip);
   if (it != clients_.end()) {
     clients_.erase(it);
   }
 }
 
 NATSocketServer::Translator* NATSocketServer::Translator::FindClient(
-    const webrtc::SocketAddress& int_ip) {
+    const SocketAddress& int_ip) {
   // See if we have the requested IP, or any of our children do.
   return (clients_.find(int_ip) != clients_.end()) ? this
                                                    : nats_.FindClient(int_ip);
@@ -476,20 +471,19 @@
 }
 
 NATSocketServer::Translator* NATSocketServer::TranslatorMap::Get(
-    const webrtc::SocketAddress& ext_ip) {
+    const SocketAddress& ext_ip) {
   TranslatorMap::iterator it = find(ext_ip);
   return (it != end()) ? it->second : nullptr;
 }
 
 NATSocketServer::Translator* NATSocketServer::TranslatorMap::Add(
-    const webrtc::SocketAddress& ext_ip,
+    const SocketAddress& ext_ip,
     Translator* nat) {
   (*this)[ext_ip] = nat;
   return nat;
 }
 
-void NATSocketServer::TranslatorMap::Remove(
-    const webrtc::SocketAddress& ext_ip) {
+void NATSocketServer::TranslatorMap::Remove(const SocketAddress& ext_ip) {
   TranslatorMap::iterator it = find(ext_ip);
   if (it != end()) {
     delete it->second;
@@ -498,7 +492,7 @@
 }
 
 NATSocketServer::Translator* NATSocketServer::TranslatorMap::FindClient(
-    const webrtc::SocketAddress& int_ip) {
+    const SocketAddress& int_ip) {
   Translator* nat = nullptr;
   for (TranslatorMap::iterator it = begin(); it != end() && !nat; ++it) {
     nat = it->second->FindClient(int_ip);
@@ -506,4 +500,4 @@
   return nat;
 }
 
-}  // namespace rtc
+}  // namespace webrtc
diff --git a/p2p/test/nat_socket_factory.h b/p2p/test/nat_socket_factory.h
index f46c76e..4a4d712 100644
--- a/p2p/test/nat_socket_factory.h
+++ b/p2p/test/nat_socket_factory.h
@@ -28,7 +28,7 @@
 #include "rtc_base/socket_server.h"
 #include "rtc_base/thread.h"
 
-namespace rtc {
+namespace webrtc {
 
 const size_t kNATEncodedIPv4AddressSize = 8U;
 const size_t kNATEncodedIPv6AddressSize = 20U;
@@ -37,37 +37,38 @@
 class NATInternalSocketFactory {
  public:
   virtual ~NATInternalSocketFactory() {}
-  virtual Socket* CreateInternalSocket(int family,
-                                       int type,
-                                       const webrtc::SocketAddress& local_addr,
-                                       webrtc::SocketAddress* nat_addr) = 0;
+  virtual rtc::Socket* CreateInternalSocket(int family,
+                                            int type,
+                                            const SocketAddress& local_addr,
+                                            SocketAddress* nat_addr) = 0;
 };
 
 // Creates sockets that will send all traffic through a NAT, using an existing
 // NATServer instance running at nat_addr. The actual data is sent using sockets
 // from a socket factory, given to the constructor.
-class NATSocketFactory : public SocketFactory, public NATInternalSocketFactory {
+class NATSocketFactory : public rtc::SocketFactory,
+                         public NATInternalSocketFactory {
  public:
-  NATSocketFactory(SocketFactory* factory,
-                   const webrtc::SocketAddress& nat_udp_addr,
-                   const webrtc::SocketAddress& nat_tcp_addr);
+  NATSocketFactory(rtc::SocketFactory* factory,
+                   const SocketAddress& nat_udp_addr,
+                   const SocketAddress& nat_tcp_addr);
 
   NATSocketFactory(const NATSocketFactory&) = delete;
   NATSocketFactory& operator=(const NATSocketFactory&) = delete;
 
   // SocketFactory implementation
-  Socket* CreateSocket(int family, int type) override;
+  rtc::Socket* CreateSocket(int family, int type) override;
 
   // NATInternalSocketFactory implementation
-  Socket* CreateInternalSocket(int family,
-                               int type,
-                               const webrtc::SocketAddress& local_addr,
-                               webrtc::SocketAddress* nat_addr) override;
+  rtc::Socket* CreateInternalSocket(int family,
+                                    int type,
+                                    const SocketAddress& local_addr,
+                                    SocketAddress* nat_addr) override;
 
  private:
-  SocketFactory* factory_;
-  webrtc::SocketAddress nat_udp_addr_;
-  webrtc::SocketAddress nat_tcp_addr_;
+  rtc::SocketFactory* factory_;
+  SocketAddress nat_udp_addr_;
+  SocketAddress nat_tcp_addr_;
 };
 
 // Creates sockets that will send traffic through a NAT depending on what
@@ -85,18 +86,19 @@
 // ss->GetTranslator("99.99.99.99")->AddClient("10.0.0.3");
 // ss->GetTranslator("99.99.99.99")->GetTranslator("10.0.0.2")->
 //     AddClient("192.168.1.2");
-class NATSocketServer : public SocketServer, public NATInternalSocketFactory {
+class NATSocketServer : public rtc::SocketServer,
+                        public NATInternalSocketFactory {
  public:
   class Translator;
 
   // holds a list of NATs
-  class TranslatorMap : private std::map<webrtc::SocketAddress, Translator*> {
+  class TranslatorMap : private std::map<SocketAddress, Translator*> {
    public:
     ~TranslatorMap();
-    Translator* Get(const webrtc::SocketAddress& ext_ip);
-    Translator* Add(const webrtc::SocketAddress& ext_ip, Translator*);
-    void Remove(const webrtc::SocketAddress& ext_ip);
-    Translator* FindClient(const webrtc::SocketAddress& int_ip);
+    Translator* Get(const SocketAddress& ext_ip);
+    Translator* Add(const SocketAddress& ext_ip, Translator*);
+    void Remove(const SocketAddress& ext_ip);
+    Translator* FindClient(const SocketAddress& int_ip);
   };
 
   // a specific NAT
@@ -104,79 +106,91 @@
    public:
     Translator(NATSocketServer* server,
                NATType type,
-               const webrtc::SocketAddress& int_addr,
-               Thread& external_socket_thread,
-               SocketFactory* ext_factory,
-               const webrtc::SocketAddress& ext_addr);
+               const SocketAddress& int_addr,
+               rtc::Thread& external_socket_thread,
+               rtc::SocketFactory* ext_factory,
+               const SocketAddress& ext_addr);
     ~Translator();
 
-    SocketFactory* internal_factory() { return internal_server_.get(); }
-    webrtc::SocketAddress internal_udp_address() const {
+    rtc::SocketFactory* internal_factory() { return internal_server_.get(); }
+    SocketAddress internal_udp_address() const {
       return nat_server_->internal_udp_address();
     }
-    webrtc::SocketAddress internal_tcp_address() const {
-      return webrtc::SocketAddress();  // nat_server_->internal_tcp_address();
+    SocketAddress internal_tcp_address() const {
+      return SocketAddress();  // nat_server_->internal_tcp_address();
     }
 
-    Translator* GetTranslator(const webrtc::SocketAddress& ext_ip);
-    Translator* AddTranslator(const webrtc::SocketAddress& ext_ip,
-                              const webrtc::SocketAddress& int_ip,
+    Translator* GetTranslator(const SocketAddress& ext_ip);
+    Translator* AddTranslator(const SocketAddress& ext_ip,
+                              const SocketAddress& int_ip,
                               NATType type);
-    void RemoveTranslator(const webrtc::SocketAddress& ext_ip);
+    void RemoveTranslator(const SocketAddress& ext_ip);
 
-    bool AddClient(const webrtc::SocketAddress& int_ip);
-    void RemoveClient(const webrtc::SocketAddress& int_ip);
+    bool AddClient(const SocketAddress& int_ip);
+    void RemoveClient(const SocketAddress& int_ip);
 
     // Looks for the specified client in this or a child NAT.
-    Translator* FindClient(const webrtc::SocketAddress& int_ip);
+    Translator* FindClient(const SocketAddress& int_ip);
 
    private:
     NATSocketServer* server_;
-    std::unique_ptr<SocketServer> internal_server_;
+    std::unique_ptr<rtc::SocketServer> internal_server_;
     std::unique_ptr<NATServer> nat_server_;
     TranslatorMap nats_;
-    std::set<webrtc::SocketAddress> clients_;
+    std::set<SocketAddress> clients_;
   };
 
-  explicit NATSocketServer(SocketServer* ss);
+  explicit NATSocketServer(rtc::SocketServer* ss);
 
   NATSocketServer(const NATSocketServer&) = delete;
   NATSocketServer& operator=(const NATSocketServer&) = delete;
 
-  SocketServer* socketserver() { return server_; }
-  Thread* queue() { return msg_queue_; }
+  rtc::SocketServer* socketserver() { return server_; }
+  rtc::Thread* queue() { return msg_queue_; }
 
-  Translator* GetTranslator(const webrtc::SocketAddress& ext_ip);
-  Translator* AddTranslator(const webrtc::SocketAddress& ext_ip,
-                            const webrtc::SocketAddress& int_ip,
+  Translator* GetTranslator(const SocketAddress& ext_ip);
+  Translator* AddTranslator(const SocketAddress& ext_ip,
+                            const SocketAddress& int_ip,
                             NATType type);
-  void RemoveTranslator(const webrtc::SocketAddress& ext_ip);
+  void RemoveTranslator(const SocketAddress& ext_ip);
 
   // SocketServer implementation
-  Socket* CreateSocket(int family, int type) override;
+  rtc::Socket* CreateSocket(int family, int type) override;
 
-  void SetMessageQueue(Thread* queue) override;
-  bool Wait(webrtc::TimeDelta max_wait_duration, bool process_io) override;
+  void SetMessageQueue(rtc::Thread* queue) override;
+  bool Wait(TimeDelta max_wait_duration, bool process_io) override;
   void WakeUp() override;
 
   // NATInternalSocketFactory implementation
-  Socket* CreateInternalSocket(int family,
-                               int type,
-                               const webrtc::SocketAddress& local_addr,
-                               webrtc::SocketAddress* nat_addr) override;
+  rtc::Socket* CreateInternalSocket(int family,
+                                    int type,
+                                    const SocketAddress& local_addr,
+                                    SocketAddress* nat_addr) override;
 
  private:
-  SocketServer* server_;
-  Thread* msg_queue_;
+  rtc::SocketServer* server_;
+  rtc::Thread* msg_queue_;
   TranslatorMap nats_;
 };
 
 // Free-standing NAT helper functions.
 size_t PackAddressForNAT(char* buf,
                          size_t buf_size,
-                         const webrtc::SocketAddress& remote_addr);
+                         const SocketAddress& remote_addr);
 size_t UnpackAddressFromNAT(rtc::ArrayView<const uint8_t> buf,
-                            webrtc::SocketAddress* remote_addr);
+                            SocketAddress* remote_addr);
+}  //  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::kNATEncodedIPv4AddressSize;
+using ::webrtc::kNATEncodedIPv6AddressSize;
+using ::webrtc::NATInternalSocketFactory;
+using ::webrtc::NATSocketFactory;
+using ::webrtc::NATSocketServer;
+using ::webrtc::PackAddressForNAT;
+using ::webrtc::UnpackAddressFromNAT;
 }  // namespace rtc
 
 #endif  // P2P_TEST_NAT_SOCKET_FACTORY_H_
diff --git a/p2p/test/nat_types.cc b/p2p/test/nat_types.cc
index 250ea22..6fbc973 100644
--- a/p2p/test/nat_types.cc
+++ b/p2p/test/nat_types.cc
@@ -12,7 +12,7 @@
 
 #include "rtc_base/checks.h"
 
-namespace rtc {
+namespace webrtc {
 
 class SymmetricNAT : public NAT {
  public:
@@ -58,4 +58,4 @@
   }
 }
 
-}  // namespace rtc
+}  // namespace webrtc
diff --git a/p2p/test/nat_types.h b/p2p/test/nat_types.h
index 7f32566..7ed5c40 100644
--- a/p2p/test/nat_types.h
+++ b/p2p/test/nat_types.h
@@ -11,7 +11,7 @@
 #ifndef P2P_TEST_NAT_TYPES_H_
 #define P2P_TEST_NAT_TYPES_H_
 
-namespace rtc {
+namespace webrtc {
 
 /* Identifies each type of NAT that can be simulated. */
 enum NATType {
@@ -42,6 +42,17 @@
   static NAT* Create(NATType type);
 };
 
+}  //  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::NAT;
+using ::webrtc::NAT_ADDR_RESTRICTED;
+using ::webrtc::NAT_OPEN_CONE;
+using ::webrtc::NAT_PORT_RESTRICTED;
+using ::webrtc::NAT_SYMMETRIC;
+using ::webrtc::NATType;
 }  // namespace rtc
 
 #endif  // P2P_TEST_NAT_TYPES_H_
diff --git a/p2p/test/nat_unittest.cc b/p2p/test/nat_unittest.cc
index e39620f..e49cbef 100644
--- a/p2p/test/nat_unittest.cc
+++ b/p2p/test/nat_unittest.cc
@@ -70,7 +70,7 @@
               const webrtc::SocketAddress& internal_addr,
               SocketServer* external,
               const webrtc::SocketAddress external_addrs[4],
-              NATType nat_type,
+              webrtc::NATType nat_type,
               bool exp_same) {
   Thread th_int(internal);
   Thread th_ext(external);
@@ -80,10 +80,10 @@
 
   webrtc::SocketAddress server_addr = internal_addr;
   server_addr.SetPort(0);  // Auto-select a port
-  NATServer* nat =
-      new NATServer(nat_type, th_int, internal, server_addr, server_addr,
-                    th_ext, external, external_addrs[0]);
-  NATSocketFactory* natsf = new NATSocketFactory(
+  webrtc::NATServer* nat =
+      new webrtc::NATServer(nat_type, th_int, internal, server_addr,
+                            server_addr, th_ext, external, external_addrs[0]);
+  webrtc::NATSocketFactory* natsf = new webrtc::NATSocketFactory(
       internal, nat->internal_udp_address(), nat->internal_tcp_address());
 
   webrtc::TestClient* in;
@@ -131,7 +131,7 @@
               const webrtc::SocketAddress& internal_addr,
               SocketServer* external,
               const webrtc::SocketAddress external_addrs[4],
-              NATType nat_type,
+              webrtc::NATType nat_type,
               bool filter_ip,
               bool filter_port) {
   Thread th_int(internal);
@@ -141,10 +141,10 @@
   server_addr.SetPort(0);  // Auto-select a port
   th_int.Start();
   th_ext.Start();
-  NATServer* nat =
-      new NATServer(nat_type, th_int, internal, server_addr, server_addr,
-                    th_ext, external, external_addrs[0]);
-  NATSocketFactory* natsf = new NATSocketFactory(
+  webrtc::NATServer* nat =
+      new webrtc::NATServer(nat_type, th_int, internal, server_addr,
+                            server_addr, th_ext, external, external_addrs[0]);
+  webrtc::NATSocketFactory* natsf = new webrtc::NATSocketFactory(
       internal, nat->internal_udp_address(), nat->internal_tcp_address());
 
   webrtc::TestClient* in = nullptr;
@@ -193,14 +193,14 @@
                   const webrtc::SocketAddress& internal_addr,
                   SocketServer* external,
                   const webrtc::SocketAddress external_addrs[4]) {
-  TestSend(internal, internal_addr, external, external_addrs, NAT_OPEN_CONE,
-           true);
   TestSend(internal, internal_addr, external, external_addrs,
-           NAT_ADDR_RESTRICTED, true);
+           webrtc::NAT_OPEN_CONE, true);
   TestSend(internal, internal_addr, external, external_addrs,
-           NAT_PORT_RESTRICTED, true);
-  TestSend(internal, internal_addr, external, external_addrs, NAT_SYMMETRIC,
-           false);
+           webrtc::NAT_ADDR_RESTRICTED, true);
+  TestSend(internal, internal_addr, external, external_addrs,
+           webrtc::NAT_PORT_RESTRICTED, true);
+  TestSend(internal, internal_addr, external, external_addrs,
+           webrtc::NAT_SYMMETRIC, false);
 }
 
 // Tests that NATServer filters packets properly.
@@ -208,14 +208,14 @@
                  const webrtc::SocketAddress& internal_addr,
                  SocketServer* external,
                  const webrtc::SocketAddress external_addrs[4]) {
-  TestRecv(internal, internal_addr, external, external_addrs, NAT_OPEN_CONE,
-           false, false);
   TestRecv(internal, internal_addr, external, external_addrs,
-           NAT_ADDR_RESTRICTED, true, false);
+           webrtc::NAT_OPEN_CONE, false, false);
   TestRecv(internal, internal_addr, external, external_addrs,
-           NAT_PORT_RESTRICTED, true, true);
-  TestRecv(internal, internal_addr, external, external_addrs, NAT_SYMMETRIC,
-           true, true);
+           webrtc::NAT_ADDR_RESTRICTED, true, false);
+  TestRecv(internal, internal_addr, external, external_addrs,
+           webrtc::NAT_PORT_RESTRICTED, true, true);
+  TestRecv(internal, internal_addr, external, external_addrs,
+           webrtc::NAT_SYMMETRIC, true, true);
 }
 
 bool TestConnectivity(const webrtc::SocketAddress& src,
@@ -357,17 +357,17 @@
         ext_vss_(new TestVirtualSocketServer()),
         int_thread_(new Thread(int_vss_.get())),
         ext_thread_(new Thread(ext_vss_.get())),
-        nat_(new NATServer(NAT_OPEN_CONE,
-                           *int_thread_,
-                           int_vss_.get(),
-                           int_addr_,
-                           int_addr_,
-                           *ext_thread_,
-                           ext_vss_.get(),
-                           ext_addr_)),
-        natsf_(new NATSocketFactory(int_vss_.get(),
-                                    nat_->internal_udp_address(),
-                                    nat_->internal_tcp_address())) {
+        nat_(new webrtc::NATServer(webrtc::NAT_OPEN_CONE,
+                                   *int_thread_,
+                                   int_vss_.get(),
+                                   int_addr_,
+                                   int_addr_,
+                                   *ext_thread_,
+                                   ext_vss_.get(),
+                                   ext_addr_)),
+        natsf_(new webrtc::NATSocketFactory(int_vss_.get(),
+                                            nat_->internal_udp_address(),
+                                            nat_->internal_tcp_address())) {
     int_thread_->Start();
     ext_thread_->Start();
   }
@@ -392,8 +392,8 @@
   std::unique_ptr<TestVirtualSocketServer> ext_vss_;
   std::unique_ptr<Thread> int_thread_;
   std::unique_ptr<Thread> ext_thread_;
-  std::unique_ptr<NATServer> nat_;
-  std::unique_ptr<NATSocketFactory> natsf_;
+  std::unique_ptr<webrtc::NATServer> nat_;
+  std::unique_ptr<webrtc::NATSocketFactory> natsf_;
   std::unique_ptr<Socket> client_;
   std::unique_ptr<Socket> server_;
   std::unique_ptr<Socket> accepted_;
diff --git a/p2p/test/stun_server.cc b/p2p/test/stun_server.cc
index 60ec70f..4299a3d 100644
--- a/p2p/test/stun_server.cc
+++ b/p2p/test/stun_server.cc
@@ -20,7 +20,7 @@
 #include "rtc_base/logging.h"
 #include "rtc_base/network/received_packet.h"
 
-namespace cricket {
+namespace webrtc {
 
 StunServer::StunServer(rtc::AsyncUDPSocket* socket) : socket_(socket) {
   socket_->RegisterReceivedPacketCallback(
@@ -39,7 +39,7 @@
   RTC_DCHECK_RUN_ON(&sequence_checker_);
   // Parse the STUN message; eat any messages that fail to parse.
   rtc::ByteBufferReader bbuf(packet.payload());
-  StunMessage msg;
+  cricket::StunMessage msg;
   if (!msg.Read(&bbuf)) {
     return;
   }
@@ -50,7 +50,7 @@
 
   // Send the message to the appropriate handler function.
   switch (msg.type()) {
-    case STUN_BINDING_REQUEST:
+    case cricket::STUN_BINDING_REQUEST:
       OnBindingRequest(&msg, packet.source_address());
       break;
 
@@ -60,21 +60,22 @@
   }
 }
 
-void StunServer::OnBindingRequest(StunMessage* msg,
-                                  const webrtc::SocketAddress& remote_addr) {
-  StunMessage response(STUN_BINDING_RESPONSE, msg->transaction_id());
+void StunServer::OnBindingRequest(cricket::StunMessage* msg,
+                                  const SocketAddress& remote_addr) {
+  cricket::StunMessage response(cricket::STUN_BINDING_RESPONSE,
+                                msg->transaction_id());
   GetStunBindResponse(msg, remote_addr, &response);
   SendResponse(response, remote_addr);
 }
 
-void StunServer::SendErrorResponse(const StunMessage& msg,
-                                   const webrtc::SocketAddress& addr,
+void StunServer::SendErrorResponse(const cricket::StunMessage& msg,
+                                   const SocketAddress& addr,
                                    int error_code,
                                    absl::string_view error_desc) {
-  StunMessage err_msg(GetStunErrorResponseType(msg.type()),
-                      msg.transaction_id());
+  cricket::StunMessage err_msg(cricket::GetStunErrorResponseType(msg.type()),
+                               msg.transaction_id());
 
-  auto err_code = StunAttribute::CreateErrorCode();
+  auto err_code = cricket::StunAttribute::CreateErrorCode();
   err_code->SetCode(error_code);
   err_code->SetReason(std::string(error_desc));
   err_msg.AddAttribute(std::move(err_code));
@@ -82,8 +83,8 @@
   SendResponse(err_msg, addr);
 }
 
-void StunServer::SendResponse(const StunMessage& msg,
-                              const webrtc::SocketAddress& addr) {
+void StunServer::SendResponse(const cricket::StunMessage& msg,
+                              const SocketAddress& addr) {
   rtc::ByteBufferWriter buf;
   msg.Write(&buf);
   rtc::PacketOptions options;
@@ -91,21 +92,23 @@
     RTC_LOG_ERR(LS_ERROR) << "sendto";
 }
 
-void StunServer::GetStunBindResponse(StunMessage* message,
-                                     const webrtc::SocketAddress& remote_addr,
-                                     StunMessage* response) const {
-  RTC_DCHECK_EQ(response->type(), STUN_BINDING_RESPONSE);
+void StunServer::GetStunBindResponse(cricket::StunMessage* message,
+                                     const SocketAddress& remote_addr,
+                                     cricket::StunMessage* response) const {
+  RTC_DCHECK_EQ(response->type(), cricket::STUN_BINDING_RESPONSE);
   RTC_DCHECK_EQ(response->transaction_id(), message->transaction_id());
 
   // Tell the user the address that we received their message from.
-  std::unique_ptr<StunAddressAttribute> mapped_addr;
+  std::unique_ptr<cricket::StunAddressAttribute> mapped_addr;
   if (message->IsLegacy()) {
-    mapped_addr = StunAttribute::CreateAddress(STUN_ATTR_MAPPED_ADDRESS);
+    mapped_addr = cricket::StunAttribute::CreateAddress(
+        cricket::STUN_ATTR_MAPPED_ADDRESS);
   } else {
-    mapped_addr = StunAttribute::CreateXorAddress(STUN_ATTR_XOR_MAPPED_ADDRESS);
+    mapped_addr = cricket::StunAttribute::CreateXorAddress(
+        cricket::STUN_ATTR_XOR_MAPPED_ADDRESS);
   }
   mapped_addr->SetAddress(remote_addr);
   response->AddAttribute(std::move(mapped_addr));
 }
 
-}  // namespace cricket
+}  // namespace webrtc
diff --git a/p2p/test/stun_server.h b/p2p/test/stun_server.h
index 4e63388..06346ad 100644
--- a/p2p/test/stun_server.h
+++ b/p2p/test/stun_server.h
@@ -21,7 +21,7 @@
 #include "rtc_base/async_udp_socket.h"
 #include "rtc_base/socket_address.h"
 
-namespace cricket {
+namespace webrtc {
 
 const int STUN_SERVER_PORT = 3478;
 
@@ -38,32 +38,39 @@
                 const rtc::ReceivedPacket& packet);
 
   // Handlers for the different types of STUN/TURN requests:
-  virtual void OnBindingRequest(StunMessage* msg,
-                                const webrtc::SocketAddress& addr);
-  void OnAllocateRequest(StunMessage* msg, const webrtc::SocketAddress& addr);
-  void OnSharedSecretRequest(StunMessage* msg,
-                             const webrtc::SocketAddress& addr);
-  void OnSendRequest(StunMessage* msg, const webrtc::SocketAddress& addr);
+  virtual void OnBindingRequest(cricket::StunMessage* msg,
+                                const SocketAddress& addr);
+  void OnAllocateRequest(cricket::StunMessage* msg, const SocketAddress& addr);
+  void OnSharedSecretRequest(cricket::StunMessage* msg,
+                             const SocketAddress& addr);
+  void OnSendRequest(cricket::StunMessage* msg, const SocketAddress& addr);
 
   // Sends an error response to the given message back to the user.
-  void SendErrorResponse(const StunMessage& msg,
-                         const webrtc::SocketAddress& addr,
+  void SendErrorResponse(const cricket::StunMessage& msg,
+                         const SocketAddress& addr,
                          int error_code,
                          absl::string_view error_desc);
 
   // Sends the given message to the appropriate destination.
-  void SendResponse(const StunMessage& msg, const webrtc::SocketAddress& addr);
+  void SendResponse(const cricket::StunMessage& msg, const SocketAddress& addr);
 
   // A helper method to compose a STUN binding response.
-  void GetStunBindResponse(StunMessage* message,
-                           const webrtc::SocketAddress& remote_addr,
-                           StunMessage* response) const;
+  void GetStunBindResponse(cricket::StunMessage* message,
+                           const SocketAddress& remote_addr,
+                           cricket::StunMessage* response) const;
 
  private:
-  webrtc::SequenceChecker sequence_checker_;
+  SequenceChecker sequence_checker_;
   std::unique_ptr<rtc::AsyncUDPSocket> socket_;
 };
 
+}  //  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::STUN_SERVER_PORT;
+using ::webrtc::StunServer;
 }  // namespace cricket
 
 #endif  // P2P_TEST_STUN_SERVER_H_
diff --git a/p2p/test/stun_server_unittest.cc b/p2p/test/stun_server_unittest.cc
index 74bdd35..a53c803 100644
--- a/p2p/test/stun_server_unittest.cc
+++ b/p2p/test/stun_server_unittest.cc
@@ -24,11 +24,11 @@
 #include "rtc_base/virtual_socket_server.h"
 #include "test/gtest.h"
 
-namespace cricket {
+namespace webrtc {
 
 namespace {
-const webrtc::SocketAddress server_addr("99.99.99.1", 3478);
-const webrtc::SocketAddress client_addr("1.2.3.4", 1234);
+const SocketAddress server_addr("99.99.99.1", 3478);
+const SocketAddress client_addr("1.2.3.4", 1234);
 }  // namespace
 
 class StunServerTest : public ::testing::Test {
@@ -37,11 +37,11 @@
     ss_->SetMessageQueue(&main_thread);
     server_.reset(
         new StunServer(rtc::AsyncUDPSocket::Create(ss_.get(), server_addr)));
-    client_.reset(new rtc::TestClient(
+    client_.reset(new TestClient(
         absl::WrapUnique(rtc::AsyncUDPSocket::Create(ss_.get(), client_addr))));
   }
 
-  void Send(const StunMessage& msg) {
+  void Send(const cricket::StunMessage& msg) {
     rtc::ByteBufferWriter buf;
     msg.Write(&buf);
     Send(reinterpret_cast<const char*>(buf.Data()),
@@ -51,13 +51,13 @@
     client_->SendTo(buf, len, server_addr);
   }
   bool ReceiveFails() { return (client_->CheckNoPacket()); }
-  StunMessage* Receive() {
-    StunMessage* msg = NULL;
-    std::unique_ptr<rtc::TestClient::Packet> packet =
-        client_->NextPacket(rtc::TestClient::kTimeoutMs);
+  cricket::StunMessage* Receive() {
+    cricket::StunMessage* msg = NULL;
+    std::unique_ptr<TestClient::Packet> packet =
+        client_->NextPacket(TestClient::kTimeoutMs);
     if (packet) {
       rtc::ByteBufferReader buf(packet->buf);
-      msg = new StunMessage();
+      msg = new cricket::StunMessage();
       msg->Read(&buf);
     }
     return msg;
@@ -67,22 +67,22 @@
   rtc::AutoThread main_thread;
   std::unique_ptr<rtc::VirtualSocketServer> ss_;
   std::unique_ptr<StunServer> server_;
-  std::unique_ptr<rtc::TestClient> client_;
+  std::unique_ptr<TestClient> client_;
 };
 
 TEST_F(StunServerTest, TestGood) {
   // kStunLegacyTransactionIdLength = 16 for legacy RFC 3489 request
   std::string transaction_id = "0123456789abcdef";
-  StunMessage req(STUN_BINDING_REQUEST, transaction_id);
+  cricket::StunMessage req(cricket::STUN_BINDING_REQUEST, transaction_id);
   Send(req);
 
-  StunMessage* msg = Receive();
+  cricket::StunMessage* msg = Receive();
   ASSERT_TRUE(msg != NULL);
-  EXPECT_EQ(STUN_BINDING_RESPONSE, msg->type());
+  EXPECT_EQ(cricket::STUN_BINDING_RESPONSE, msg->type());
   EXPECT_EQ(req.transaction_id(), msg->transaction_id());
 
-  const StunAddressAttribute* mapped_addr =
-      msg->GetAddress(STUN_ATTR_MAPPED_ADDRESS);
+  const cricket::StunAddressAttribute* mapped_addr =
+      msg->GetAddress(cricket::STUN_ATTR_MAPPED_ADDRESS);
   EXPECT_TRUE(mapped_addr != NULL);
   EXPECT_EQ(1, mapped_addr->family());
   EXPECT_EQ(client_addr.port(), mapped_addr->port());
@@ -94,16 +94,16 @@
   // kStunTransactionIdLength = 12 for RFC 5389 request
   // StunMessage::Write will automatically insert magic cookie (0x2112A442)
   std::string transaction_id = "0123456789ab";
-  StunMessage req(STUN_BINDING_REQUEST, transaction_id);
+  cricket::StunMessage req(cricket::STUN_BINDING_REQUEST, transaction_id);
   Send(req);
 
-  StunMessage* msg = Receive();
+  cricket::StunMessage* msg = Receive();
   ASSERT_TRUE(msg != NULL);
-  EXPECT_EQ(STUN_BINDING_RESPONSE, msg->type());
+  EXPECT_EQ(cricket::STUN_BINDING_RESPONSE, msg->type());
   EXPECT_EQ(req.transaction_id(), msg->transaction_id());
 
-  const StunAddressAttribute* mapped_addr =
-      msg->GetAddress(STUN_ATTR_XOR_MAPPED_ADDRESS);
+  const cricket::StunAddressAttribute* mapped_addr =
+      msg->GetAddress(cricket::STUN_ATTR_XOR_MAPPED_ADDRESS);
   EXPECT_TRUE(mapped_addr != NULL);
   EXPECT_EQ(1, mapped_addr->family());
   EXPECT_EQ(client_addr.port(), mapped_addr->port());
@@ -115,16 +115,16 @@
 TEST_F(StunServerTest, TestNoXorMappedAddr) {
   // kStunLegacyTransactionIdLength = 16 for legacy RFC 3489 request
   std::string transaction_id = "0123456789abcdef";
-  StunMessage req(STUN_BINDING_REQUEST, transaction_id);
+  cricket::StunMessage req(cricket::STUN_BINDING_REQUEST, transaction_id);
   Send(req);
 
-  StunMessage* msg = Receive();
+  cricket::StunMessage* msg = Receive();
   ASSERT_TRUE(msg != NULL);
-  EXPECT_EQ(STUN_BINDING_RESPONSE, msg->type());
+  EXPECT_EQ(cricket::STUN_BINDING_RESPONSE, msg->type());
   EXPECT_EQ(req.transaction_id(), msg->transaction_id());
 
-  const StunAddressAttribute* mapped_addr =
-      msg->GetAddress(STUN_ATTR_XOR_MAPPED_ADDRESS);
+  const cricket::StunAddressAttribute* mapped_addr =
+      msg->GetAddress(cricket::STUN_ATTR_XOR_MAPPED_ADDRESS);
   EXPECT_TRUE(mapped_addr == NULL);
 
   delete msg;
@@ -140,4 +140,4 @@
   ASSERT_TRUE(ReceiveFails());
 }
 
-}  // namespace cricket
+}  // namespace webrtc
diff --git a/p2p/test/test_stun_server.cc b/p2p/test/test_stun_server.cc
index 2a835e3..38ca094 100644
--- a/p2p/test/test_stun_server.cc
+++ b/p2p/test/test_stun_server.cc
@@ -15,11 +15,11 @@
 #include "rtc_base/socket.h"
 #include "rtc_base/socket_server.h"
 
-namespace cricket {
+namespace webrtc {
 
-std::unique_ptr<TestStunServer, std::function<void(TestStunServer*)>>
+std::unique_ptr<TestStunServer, std::function<void(webrtc::TestStunServer*)>>
 TestStunServer::Create(rtc::SocketServer* ss,
-                       const webrtc::SocketAddress& addr,
+                       const SocketAddress& addr,
                        rtc::Thread& network_thread) {
   rtc::Socket* socket = ss->CreateSocket(addr.family(), SOCK_DGRAM);
   RTC_CHECK(socket != nullptr) << "Failed to create socket";
@@ -28,24 +28,24 @@
   TestStunServer* server = nullptr;
   network_thread.BlockingCall(
       [&]() { server = new TestStunServer(udp_socket, network_thread); });
-  std::unique_ptr<TestStunServer, std::function<void(TestStunServer*)>> result(
-      server, [&](TestStunServer* server) {
+  std::unique_ptr<TestStunServer, std::function<void(webrtc::TestStunServer*)>>
+      result(server, [&](TestStunServer* server) {
         network_thread.BlockingCall([server]() { delete server; });
       });
   return result;
 }
 
-void TestStunServer::OnBindingRequest(
-    StunMessage* msg,
-    const webrtc::SocketAddress& remote_addr) {
+void TestStunServer::OnBindingRequest(cricket::StunMessage* msg,
+                                      const SocketAddress& remote_addr) {
   RTC_DCHECK_RUN_ON(&network_thread_);
   if (fake_stun_addr_.IsNil()) {
     StunServer::OnBindingRequest(msg, remote_addr);
   } else {
-    StunMessage response(STUN_BINDING_RESPONSE, msg->transaction_id());
+    cricket::StunMessage response(cricket::STUN_BINDING_RESPONSE,
+                                  msg->transaction_id());
     GetStunBindResponse(msg, fake_stun_addr_, &response);
     SendResponse(response, remote_addr);
   }
 }
 
-}  // namespace cricket
+}  // namespace webrtc
diff --git a/p2p/test/test_stun_server.h b/p2p/test/test_stun_server.h
index f90958a..cef3ea2 100644
--- a/p2p/test/test_stun_server.h
+++ b/p2p/test/test_stun_server.h
@@ -20,21 +20,20 @@
 #include "rtc_base/socket_server.h"
 #include "rtc_base/thread.h"
 
-namespace cricket {
+namespace webrtc {
 
 // A test STUN server. Useful for unit tests.
 class TestStunServer : StunServer {
  public:
   using StunServerPtr =
-      std::unique_ptr<TestStunServer, std::function<void(TestStunServer*)>>;
+      std::unique_ptr<TestStunServer,
+                      std::function<void(webrtc::TestStunServer*)>>;
   static StunServerPtr Create(rtc::SocketServer* ss,
-                              const webrtc::SocketAddress& addr,
+                              const SocketAddress& addr,
                               rtc::Thread& network_thread);
 
   // Set a fake STUN address to return to the client.
-  void set_fake_stun_addr(const webrtc::SocketAddress& addr) {
-    fake_stun_addr_ = addr;
-  }
+  void set_fake_stun_addr(const SocketAddress& addr) { fake_stun_addr_ = addr; }
 
  private:
   static void DeleteOnNetworkThread(TestStunServer* server);
@@ -42,14 +41,20 @@
   TestStunServer(rtc::AsyncUDPSocket* socket, rtc::Thread& network_thread)
       : StunServer(socket), network_thread_(network_thread) {}
 
-  void OnBindingRequest(StunMessage* msg,
-                        const webrtc::SocketAddress& remote_addr) override;
+  void OnBindingRequest(cricket::StunMessage* msg,
+                        const SocketAddress& remote_addr) override;
 
  private:
-  webrtc::SocketAddress fake_stun_addr_;
+  SocketAddress fake_stun_addr_;
   rtc::Thread& network_thread_;
 };
 
+}  //  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::TestStunServer;
 }  // namespace cricket
 
 #endif  // P2P_TEST_TEST_STUN_SERVER_H_
diff --git a/p2p/test/test_turn_customizer.h b/p2p/test/test_turn_customizer.h
index 4ab2420..0ec8764 100644
--- a/p2p/test/test_turn_customizer.h
+++ b/p2p/test/test_turn_customizer.h
@@ -16,9 +16,9 @@
 #include "api/turn_customizer.h"
 #include "rtc_base/gunit.h"
 
-namespace cricket {
+namespace webrtc {
 
-class TestTurnCustomizer : public webrtc::TurnCustomizer {
+class TestTurnCustomizer : public TurnCustomizer {
  public:
   TestTurnCustomizer() {}
   virtual ~TestTurnCustomizer() {}
@@ -28,7 +28,7 @@
     STUN_ATTR_COUNTER = 0xFF02  // Number
   };
 
-  void MaybeModifyOutgoingStunMessage(webrtc::PortInterface* port,
+  void MaybeModifyOutgoingStunMessage(PortInterface* port,
                                       cricket::StunMessage* message) override {
     modify_cnt_++;
 
@@ -40,7 +40,7 @@
     return;
   }
 
-  bool AllowChannelData(webrtc::PortInterface* port,
+  bool AllowChannelData(PortInterface* port,
                         const void* data,
                         size_t size,
                         bool payload) override {
@@ -54,6 +54,12 @@
   unsigned int allow_channel_data_cnt_ = 0;
 };
 
+}  //  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::TestTurnCustomizer;
 }  // namespace cricket
 
 #endif  // P2P_TEST_TEST_TURN_CUSTOMIZER_H_
diff --git a/p2p/test/test_turn_server.h b/p2p/test/test_turn_server.h
index 91dc926..6e4821b 100644
--- a/p2p/test/test_turn_server.h
+++ b/p2p/test/test_turn_server.h
@@ -26,20 +26,18 @@
 #include "rtc_base/ssl_identity.h"
 #include "rtc_base/thread.h"
 
-namespace cricket {
+namespace webrtc {
 
 static const char kTestRealm[] = "example.org";
 static const char kTestSoftware[] = "TestTurnServer";
 
 class TestTurnRedirector : public TurnRedirectInterface {
  public:
-  explicit TestTurnRedirector(
-      const std::vector<webrtc::SocketAddress>& addresses)
+  explicit TestTurnRedirector(const std::vector<SocketAddress>& addresses)
       : alternate_server_addresses_(addresses),
         iter_(alternate_server_addresses_.begin()) {}
 
-  virtual bool ShouldRedirect(const webrtc::SocketAddress&,
-                              webrtc::SocketAddress* out) {
+  virtual bool ShouldRedirect(const SocketAddress&, SocketAddress* out) {
     if (!out || iter_ == alternate_server_addresses_.end()) {
       return false;
     }
@@ -48,17 +46,17 @@
   }
 
  private:
-  const std::vector<webrtc::SocketAddress>& alternate_server_addresses_;
-  std::vector<webrtc::SocketAddress>::const_iterator iter_;
+  const std::vector<SocketAddress>& alternate_server_addresses_;
+  std::vector<SocketAddress>::const_iterator iter_;
 };
 
 class TestTurnServer : public TurnAuthInterface {
  public:
   TestTurnServer(rtc::Thread* thread,
                  rtc::SocketFactory* socket_factory,
-                 const webrtc::SocketAddress& int_addr,
-                 const webrtc::SocketAddress& udp_ext_addr,
-                 webrtc::ProtocolType int_protocol = webrtc::PROTO_UDP,
+                 const SocketAddress& int_addr,
+                 const SocketAddress& udp_ext_addr,
+                 ProtocolType int_protocol = webrtc::PROTO_UDP,
                  bool ignore_bad_cert = true,
                  absl::string_view common_name = "test turn server")
       : server_(thread), socket_factory_(socket_factory) {
@@ -92,8 +90,8 @@
     server_.set_enable_permission_checks(enable);
   }
 
-  void AddInternalSocket(const webrtc::SocketAddress& int_addr,
-                         webrtc::ProtocolType proto,
+  void AddInternalSocket(const SocketAddress& int_addr,
+                         ProtocolType proto,
                          bool ignore_bad_cert = true,
                          absl::string_view common_name = "test turn server") {
     RTC_DCHECK(thread_checker_.IsCurrent());
@@ -129,7 +127,7 @@
 
   // Finds the first allocation in the server allocation map with a source
   // ip and port matching the socket address provided.
-  TurnServerAllocation* FindAllocation(const webrtc::SocketAddress& src) {
+  TurnServerAllocation* FindAllocation(const SocketAddress& src) {
     RTC_DCHECK(thread_checker_.IsCurrent());
     const TurnServer::AllocationMap& map = server_.allocations();
     for (TurnServer::AllocationMap::const_iterator it = map.begin();
@@ -148,15 +146,24 @@
                       absl::string_view realm,
                       std::string* key) {
     RTC_DCHECK(thread_checker_.IsCurrent());
-    return ComputeStunCredentialHash(std::string(username), std::string(realm),
-                                     std::string(username), key);
+    return cricket::ComputeStunCredentialHash(
+        std::string(username), std::string(realm), std::string(username), key);
   }
 
   TurnServer server_;
   rtc::SocketFactory* socket_factory_;
-  webrtc::SequenceChecker thread_checker_;
+  SequenceChecker thread_checker_;
 };
 
+}  //  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::kTestRealm;
+using ::webrtc::kTestSoftware;
+using ::webrtc::TestTurnRedirector;
+using ::webrtc::TestTurnServer;
 }  // namespace cricket
 
 #endif  // P2P_TEST_TEST_TURN_SERVER_H_
diff --git a/p2p/test/turn_server.cc b/p2p/test/turn_server.cc
index baff123..c560460 100644
--- a/p2p/test/turn_server.cc
+++ b/p2p/test/turn_server.cc
@@ -32,7 +32,7 @@
 #include "rtc_base/strings/string_builder.h"
 #include "rtc_base/time_utils.h"
 
-namespace cricket {
+namespace webrtc {
 namespace {
 using ::webrtc::TimeDelta;
 
@@ -56,24 +56,24 @@
 
 }  // namespace
 
-int GetStunSuccessResponseTypeOrZero(const StunMessage& req) {
-  const int resp_type = GetStunSuccessResponseType(req.type());
+int GetStunSuccessResponseTypeOrZero(const cricket::StunMessage& req) {
+  const int resp_type = cricket::GetStunSuccessResponseType(req.type());
   return resp_type == -1 ? 0 : resp_type;
 }
 
-int GetStunErrorResponseTypeOrZero(const StunMessage& req) {
-  const int resp_type = GetStunErrorResponseType(req.type());
+int GetStunErrorResponseTypeOrZero(const cricket::StunMessage& req) {
+  const int resp_type = cricket::GetStunErrorResponseType(req.type());
   return resp_type == -1 ? 0 : resp_type;
 }
 
 static void InitErrorResponse(int code,
                               absl::string_view reason,
-                              StunMessage* resp) {
+                              cricket::StunMessage* resp) {
   resp->AddAttribute(std::make_unique<cricket::StunErrorCodeAttribute>(
-      STUN_ATTR_ERROR_CODE, code, std::string(reason)));
+      cricket::STUN_ATTR_ERROR_CODE, code, std::string(reason)));
 }
 
-TurnServer::TurnServer(webrtc::TaskQueueBase* thread)
+TurnServer::TurnServer(TaskQueueBase* thread)
     : thread_(thread),
       nonce_key_(rtc::CreateRandomString(kNonceKeySize)),
       auth_hook_(NULL),
@@ -96,7 +96,7 @@
 }
 
 void TurnServer::AddInternalSocket(rtc::AsyncPacketSocket* socket,
-                                   webrtc::ProtocolType proto) {
+                                   ProtocolType proto) {
   RTC_DCHECK_RUN_ON(thread_);
   RTC_DCHECK(server_sockets_.end() == server_sockets_.find(socket));
   server_sockets_[socket] = proto;
@@ -109,7 +109,7 @@
 
 void TurnServer::AddInternalServerSocket(
     rtc::Socket* socket,
-    webrtc::ProtocolType proto,
+    ProtocolType proto,
     std::unique_ptr<rtc::SSLAdapterFactory> ssl_adapter_factory) {
   RTC_DCHECK_RUN_ON(thread_);
 
@@ -119,9 +119,8 @@
   socket->SignalReadEvent.connect(this, &TurnServer::OnNewInternalConnection);
 }
 
-void TurnServer::SetExternalSocketFactory(
-    rtc::PacketSocketFactory* factory,
-    const webrtc::SocketAddress& external_addr) {
+void TurnServer::SetExternalSocketFactory(rtc::PacketSocketFactory* factory,
+                                          const SocketAddress& external_addr) {
   RTC_DCHECK_RUN_ON(thread_);
   external_socket_factory_.reset(factory);
   external_addr_ = external_addr;
@@ -138,7 +137,7 @@
   RTC_DCHECK_RUN_ON(thread_);
 
   // Check if someone is trying to connect to us.
-  webrtc::SocketAddress accept_addr;
+  SocketAddress accept_addr;
   rtc::Socket* accepted_socket = server_socket->Accept(&accept_addr);
   if (accepted_socket != NULL) {
     const ServerSocketInfo& info = server_listen_sockets_[server_socket];
@@ -195,7 +194,7 @@
 void TurnServer::HandleStunMessage(TurnServerConnection* conn,
                                    rtc::ArrayView<const uint8_t> payload) {
   RTC_DCHECK_RUN_ON(thread_);
-  TurnMessage msg;
+  cricket::TurnMessage msg;
   rtc::ByteBufferReader buf(payload);
   if (!msg.Read(&buf) || (buf.Length() > 0)) {
     RTC_LOG(LS_WARNING) << "Received invalid STUN message";
@@ -207,13 +206,13 @@
   }
 
   // If it's a STUN binding request, handle that specially.
-  if (msg.type() == STUN_BINDING_REQUEST) {
+  if (msg.type() == cricket::STUN_BINDING_REQUEST) {
     HandleBindingRequest(conn, &msg);
     return;
   }
 
-  if (redirect_hook_ != NULL && msg.type() == STUN_ALLOCATE_REQUEST) {
-    webrtc::SocketAddress address;
+  if (redirect_hook_ != NULL && msg.type() == cricket::STUN_ALLOCATE_REQUEST) {
+    SocketAddress address;
     if (redirect_hook_->ShouldRedirect(conn->src(), &address)) {
       SendErrorResponseWithAlternateServer(conn, &msg, address);
       return;
@@ -231,37 +230,37 @@
   }
 
   // Ensure the message is authorized; only needed for requests.
-  if (IsStunRequestType(msg.type())) {
+  if (cricket::IsStunRequestType(msg.type())) {
     if (!CheckAuthorization(conn, &msg, key)) {
       return;
     }
   }
 
-  if (!allocation && msg.type() == STUN_ALLOCATE_REQUEST) {
+  if (!allocation && msg.type() == cricket::STUN_ALLOCATE_REQUEST) {
     HandleAllocateRequest(conn, &msg, key);
   } else if (allocation &&
-             (msg.type() != STUN_ALLOCATE_REQUEST ||
+             (msg.type() != cricket::STUN_ALLOCATE_REQUEST ||
               msg.transaction_id() == allocation->transaction_id())) {
     // This is a non-allocate request, or a retransmit of an allocate.
     // Check that the username matches the previous username used.
-    if (IsStunRequestType(msg.type()) &&
-        msg.GetByteString(STUN_ATTR_USERNAME)->string_view() !=
+    if (cricket::IsStunRequestType(msg.type()) &&
+        msg.GetByteString(cricket::STUN_ATTR_USERNAME)->string_view() !=
             allocation->username()) {
-      SendErrorResponse(conn, &msg, STUN_ERROR_WRONG_CREDENTIALS,
-                        STUN_ERROR_REASON_WRONG_CREDENTIALS);
+      SendErrorResponse(conn, &msg, cricket::STUN_ERROR_WRONG_CREDENTIALS,
+                        cricket::STUN_ERROR_REASON_WRONG_CREDENTIALS);
       return;
     }
     allocation->HandleTurnMessage(&msg);
   } else {
     // Allocation mismatch.
-    SendErrorResponse(conn, &msg, STUN_ERROR_ALLOCATION_MISMATCH,
-                      STUN_ERROR_REASON_ALLOCATION_MISMATCH);
+    SendErrorResponse(conn, &msg, cricket::STUN_ERROR_ALLOCATION_MISMATCH,
+                      cricket::STUN_ERROR_REASON_ALLOCATION_MISMATCH);
   }
 }
 
-bool TurnServer::GetKey(const StunMessage* msg, std::string* key) {
-  const StunByteStringAttribute* username_attr =
-      msg->GetByteString(STUN_ATTR_USERNAME);
+bool TurnServer::GetKey(const cricket::StunMessage* msg, std::string* key) {
+  const cricket::StunByteStringAttribute* username_attr =
+      msg->GetByteString(cricket::STUN_ATTR_USERNAME);
   if (!username_attr) {
     return false;
   }
@@ -272,45 +271,48 @@
 }
 
 bool TurnServer::CheckAuthorization(TurnServerConnection* conn,
-                                    StunMessage* msg,
+                                    cricket::StunMessage* msg,
                                     absl::string_view key) {
   // RFC 5389, 10.2.2.
-  RTC_DCHECK(IsStunRequestType(msg->type()));
-  const StunByteStringAttribute* mi_attr =
-      msg->GetByteString(STUN_ATTR_MESSAGE_INTEGRITY);
-  const StunByteStringAttribute* username_attr =
-      msg->GetByteString(STUN_ATTR_USERNAME);
-  const StunByteStringAttribute* realm_attr =
-      msg->GetByteString(STUN_ATTR_REALM);
-  const StunByteStringAttribute* nonce_attr =
-      msg->GetByteString(STUN_ATTR_NONCE);
+  RTC_DCHECK(cricket::IsStunRequestType(msg->type()));
+  const cricket::StunByteStringAttribute* mi_attr =
+      msg->GetByteString(cricket::STUN_ATTR_MESSAGE_INTEGRITY);
+  const cricket::StunByteStringAttribute* username_attr =
+      msg->GetByteString(cricket::STUN_ATTR_USERNAME);
+  const cricket::StunByteStringAttribute* realm_attr =
+      msg->GetByteString(cricket::STUN_ATTR_REALM);
+  const cricket::StunByteStringAttribute* nonce_attr =
+      msg->GetByteString(cricket::STUN_ATTR_NONCE);
 
   // Fail if no MESSAGE_INTEGRITY.
   if (!mi_attr) {
-    SendErrorResponseWithRealmAndNonce(conn, msg, STUN_ERROR_UNAUTHORIZED,
-                                       STUN_ERROR_REASON_UNAUTHORIZED);
+    SendErrorResponseWithRealmAndNonce(conn, msg,
+                                       cricket::STUN_ERROR_UNAUTHORIZED,
+                                       cricket::STUN_ERROR_REASON_UNAUTHORIZED);
     return false;
   }
 
   // Fail if there is MESSAGE_INTEGRITY but no username, nonce, or realm.
   if (!username_attr || !realm_attr || !nonce_attr) {
-    SendErrorResponse(conn, msg, STUN_ERROR_BAD_REQUEST,
-                      STUN_ERROR_REASON_BAD_REQUEST);
+    SendErrorResponse(conn, msg, cricket::STUN_ERROR_BAD_REQUEST,
+                      cricket::STUN_ERROR_REASON_BAD_REQUEST);
     return false;
   }
 
   // Fail if bad nonce.
   if (!ValidateNonce(nonce_attr->string_view())) {
-    SendErrorResponseWithRealmAndNonce(conn, msg, STUN_ERROR_STALE_NONCE,
-                                       STUN_ERROR_REASON_STALE_NONCE);
+    SendErrorResponseWithRealmAndNonce(conn, msg,
+                                       cricket::STUN_ERROR_STALE_NONCE,
+                                       cricket::STUN_ERROR_REASON_STALE_NONCE);
     return false;
   }
 
   // Fail if bad MESSAGE_INTEGRITY.
   if (key.empty() || msg->ValidateMessageIntegrity(std::string(key)) !=
-                         StunMessage::IntegrityStatus::kIntegrityOk) {
-    SendErrorResponseWithRealmAndNonce(conn, msg, STUN_ERROR_UNAUTHORIZED,
-                                       STUN_ERROR_REASON_UNAUTHORIZED);
+                         cricket::StunMessage::IntegrityStatus::kIntegrityOk) {
+    SendErrorResponseWithRealmAndNonce(conn, msg,
+                                       cricket::STUN_ERROR_UNAUTHORIZED,
+                                       cricket::STUN_ERROR_REASON_UNAUTHORIZED);
     return false;
   }
 
@@ -318,8 +320,9 @@
   TurnServerAllocation* allocation = FindAllocation(conn);
   if (enable_otu_nonce_ && allocation &&
       allocation->last_nonce() == nonce_attr->string_view()) {
-    SendErrorResponseWithRealmAndNonce(conn, msg, STUN_ERROR_STALE_NONCE,
-                                       STUN_ERROR_REASON_STALE_NONCE);
+    SendErrorResponseWithRealmAndNonce(conn, msg,
+                                       cricket::STUN_ERROR_STALE_NONCE,
+                                       cricket::STUN_ERROR_REASON_STALE_NONCE);
     return false;
   }
 
@@ -331,34 +334,34 @@
 }
 
 void TurnServer::HandleBindingRequest(TurnServerConnection* conn,
-                                      const StunMessage* req) {
-  StunMessage response(GetStunSuccessResponseTypeOrZero(*req),
-                       req->transaction_id());
+                                      const cricket::StunMessage* req) {
+  cricket::StunMessage response(GetStunSuccessResponseTypeOrZero(*req),
+                                req->transaction_id());
   // Tell the user the address that we received their request from.
-  auto mapped_addr_attr = std::make_unique<StunXorAddressAttribute>(
-      STUN_ATTR_XOR_MAPPED_ADDRESS, conn->src());
+  auto mapped_addr_attr = std::make_unique<cricket::StunXorAddressAttribute>(
+      cricket::STUN_ATTR_XOR_MAPPED_ADDRESS, conn->src());
   response.AddAttribute(std::move(mapped_addr_attr));
 
   SendStun(conn, &response);
 }
 
 void TurnServer::HandleAllocateRequest(TurnServerConnection* conn,
-                                       const TurnMessage* msg,
+                                       const cricket::TurnMessage* msg,
                                        absl::string_view key) {
   // Check the parameters in the request.
-  const StunUInt32Attribute* transport_attr =
-      msg->GetUInt32(STUN_ATTR_REQUESTED_TRANSPORT);
+  const cricket::StunUInt32Attribute* transport_attr =
+      msg->GetUInt32(cricket::STUN_ATTR_REQUESTED_TRANSPORT);
   if (!transport_attr) {
-    SendErrorResponse(conn, msg, STUN_ERROR_BAD_REQUEST,
-                      STUN_ERROR_REASON_BAD_REQUEST);
+    SendErrorResponse(conn, msg, cricket::STUN_ERROR_BAD_REQUEST,
+                      cricket::STUN_ERROR_REASON_BAD_REQUEST);
     return;
   }
 
   // Only UDP is supported right now.
   int proto = transport_attr->value() >> 24;
   if (proto != IPPROTO_UDP) {
-    SendErrorResponse(conn, msg, STUN_ERROR_UNSUPPORTED_PROTOCOL,
-                      STUN_ERROR_REASON_UNSUPPORTED_PROTOCOL);
+    SendErrorResponse(conn, msg, cricket::STUN_ERROR_UNSUPPORTED_PROTOCOL,
+                      cricket::STUN_ERROR_REASON_UNSUPPORTED_PROTOCOL);
     return;
   }
 
@@ -368,7 +371,7 @@
   if (alloc) {
     alloc->HandleTurnMessage(msg);
   } else {
-    SendErrorResponse(conn, msg, STUN_ERROR_SERVER_ERROR,
+    SendErrorResponse(conn, msg, cricket::STUN_ERROR_SERVER_ERROR,
                       "Failed to allocate socket");
   }
 }
@@ -433,11 +436,12 @@
 }
 
 void TurnServer::SendErrorResponse(TurnServerConnection* conn,
-                                   const StunMessage* req,
+                                   const cricket::StunMessage* req,
                                    int code,
                                    absl::string_view reason) {
   RTC_DCHECK_RUN_ON(thread_);
-  TurnMessage resp(GetStunErrorResponseTypeOrZero(*req), req->transaction_id());
+  cricket::TurnMessage resp(GetStunErrorResponseTypeOrZero(*req),
+                            req->transaction_id());
   InitErrorResponse(code, reason, &resp);
 
   RTC_LOG(LS_INFO) << "Sending error response, type=" << resp.type()
@@ -445,11 +449,13 @@
   SendStun(conn, &resp);
 }
 
-void TurnServer::SendErrorResponseWithRealmAndNonce(TurnServerConnection* conn,
-                                                    const StunMessage* msg,
-                                                    int code,
-                                                    absl::string_view reason) {
-  TurnMessage resp(GetStunErrorResponseTypeOrZero(*msg), msg->transaction_id());
+void TurnServer::SendErrorResponseWithRealmAndNonce(
+    TurnServerConnection* conn,
+    const cricket::StunMessage* msg,
+    int code,
+    absl::string_view reason) {
+  cricket::TurnMessage resp(GetStunErrorResponseTypeOrZero(*msg),
+                            msg->transaction_id());
   InitErrorResponse(code, reason, &resp);
 
   int64_t timestamp = rtc::TimeMillis();
@@ -457,32 +463,34 @@
     timestamp = ts_for_next_nonce_;
     ts_for_next_nonce_ = 0;
   }
-  resp.AddAttribute(std::make_unique<StunByteStringAttribute>(
-      STUN_ATTR_NONCE, GenerateNonce(timestamp)));
-  resp.AddAttribute(
-      std::make_unique<StunByteStringAttribute>(STUN_ATTR_REALM, realm_));
+  resp.AddAttribute(std::make_unique<cricket::StunByteStringAttribute>(
+      cricket::STUN_ATTR_NONCE, GenerateNonce(timestamp)));
+  resp.AddAttribute(std::make_unique<cricket::StunByteStringAttribute>(
+      cricket::STUN_ATTR_REALM, realm_));
   SendStun(conn, &resp);
 }
 
 void TurnServer::SendErrorResponseWithAlternateServer(
     TurnServerConnection* conn,
-    const StunMessage* msg,
-    const webrtc::SocketAddress& addr) {
-  TurnMessage resp(GetStunErrorResponseTypeOrZero(*msg), msg->transaction_id());
-  InitErrorResponse(STUN_ERROR_TRY_ALTERNATE,
-                    STUN_ERROR_REASON_TRY_ALTERNATE_SERVER, &resp);
-  resp.AddAttribute(
-      std::make_unique<StunAddressAttribute>(STUN_ATTR_ALTERNATE_SERVER, addr));
+    const cricket::StunMessage* msg,
+    const SocketAddress& addr) {
+  cricket::TurnMessage resp(GetStunErrorResponseTypeOrZero(*msg),
+                            msg->transaction_id());
+  InitErrorResponse(cricket::STUN_ERROR_TRY_ALTERNATE,
+                    cricket::STUN_ERROR_REASON_TRY_ALTERNATE_SERVER, &resp);
+  resp.AddAttribute(std::make_unique<cricket::StunAddressAttribute>(
+      cricket::STUN_ATTR_ALTERNATE_SERVER, addr));
   SendStun(conn, &resp);
 }
 
-void TurnServer::SendStun(TurnServerConnection* conn, StunMessage* msg) {
+void TurnServer::SendStun(TurnServerConnection* conn,
+                          cricket::StunMessage* msg) {
   RTC_DCHECK_RUN_ON(thread_);
   rtc::ByteBufferWriter buf;
   // Add a SOFTWARE attribute if one is set.
   if (!software_.empty()) {
-    msg->AddAttribute(std::make_unique<StunByteStringAttribute>(
-        STUN_ATTR_SOFTWARE, software_));
+    msg->AddAttribute(std::make_unique<cricket::StunByteStringAttribute>(
+        cricket::STUN_ATTR_SOFTWARE, software_));
   }
   msg->Write(&buf);
   Send(conn, buf);
@@ -526,8 +534,8 @@
   }
 }
 
-TurnServerConnection::TurnServerConnection(const webrtc::SocketAddress& src,
-                                           webrtc::ProtocolType proto,
+TurnServerConnection::TurnServerConnection(const SocketAddress& src,
+                                           ProtocolType proto,
                                            rtc::AsyncPacketSocket* socket)
     : src_(src),
       dst_(socket->GetRemoteAddress()),
@@ -544,14 +552,14 @@
 
 std::string TurnServerConnection::ToString() const {
   const char* const kProtos[] = {"unknown", "udp", "tcp", "ssltcp"};
-  rtc::StringBuilder ost;
+  StringBuilder ost;
   ost << src_.ToSensitiveString() << "-" << dst_.ToSensitiveString() << ":"
       << kProtos[proto_];
   return ost.Release();
 }
 
 TurnServerAllocation::TurnServerAllocation(TurnServer* server,
-                                           webrtc::TaskQueueBase* thread,
+                                           TaskQueueBase* thread,
                                            const TurnServerConnection& conn,
                                            rtc::AsyncPacketSocket* socket,
                                            absl::string_view key)
@@ -574,28 +582,28 @@
 }
 
 std::string TurnServerAllocation::ToString() const {
-  rtc::StringBuilder ost;
+  StringBuilder ost;
   ost << "Alloc[" << conn_.ToString() << "]";
   return ost.Release();
 }
 
-void TurnServerAllocation::HandleTurnMessage(const TurnMessage* msg) {
+void TurnServerAllocation::HandleTurnMessage(const cricket::TurnMessage* msg) {
   RTC_DCHECK_RUN_ON(thread_);
   RTC_DCHECK(msg != NULL);
   switch (msg->type()) {
-    case STUN_ALLOCATE_REQUEST:
+    case cricket::STUN_ALLOCATE_REQUEST:
       HandleAllocateRequest(msg);
       break;
-    case TURN_REFRESH_REQUEST:
+    case cricket::TURN_REFRESH_REQUEST:
       HandleRefreshRequest(msg);
       break;
-    case TURN_SEND_INDICATION:
+    case cricket::TURN_SEND_INDICATION:
       HandleSendIndication(msg);
       break;
-    case TURN_CREATE_PERMISSION_REQUEST:
+    case cricket::TURN_CREATE_PERMISSION_REQUEST:
       HandleCreatePermissionRequest(msg);
       break;
-    case TURN_CHANNEL_BIND_REQUEST:
+    case cricket::TURN_CHANNEL_BIND_REQUEST:
       HandleChannelBindRequest(msg);
       break;
     default:
@@ -606,11 +614,12 @@
   }
 }
 
-void TurnServerAllocation::HandleAllocateRequest(const TurnMessage* msg) {
+void TurnServerAllocation::HandleAllocateRequest(
+    const cricket::TurnMessage* msg) {
   // Copy the important info from the allocate request.
   transaction_id_ = msg->transaction_id();
-  const StunByteStringAttribute* username_attr =
-      msg->GetByteString(STUN_ATTR_USERNAME);
+  const cricket::StunByteStringAttribute* username_attr =
+      msg->GetByteString(cricket::STUN_ATTR_USERNAME);
   RTC_DCHECK(username_attr != NULL);
   username_ = std::string(username_attr->string_view());
 
@@ -622,15 +631,16 @@
                    << lifetime.seconds();
 
   // We've already validated all the important bits; just send a response here.
-  TurnMessage response(GetStunSuccessResponseTypeOrZero(*msg),
-                       msg->transaction_id());
+  cricket::TurnMessage response(GetStunSuccessResponseTypeOrZero(*msg),
+                                msg->transaction_id());
 
-  auto mapped_addr_attr = std::make_unique<StunXorAddressAttribute>(
-      STUN_ATTR_XOR_MAPPED_ADDRESS, conn_.src());
-  auto relayed_addr_attr = std::make_unique<StunXorAddressAttribute>(
-      STUN_ATTR_XOR_RELAYED_ADDRESS, external_socket_->GetLocalAddress());
-  auto lifetime_attr = std::make_unique<StunUInt32Attribute>(
-      STUN_ATTR_LIFETIME, lifetime.seconds());
+  auto mapped_addr_attr = std::make_unique<cricket::StunXorAddressAttribute>(
+      cricket::STUN_ATTR_XOR_MAPPED_ADDRESS, conn_.src());
+  auto relayed_addr_attr = std::make_unique<cricket::StunXorAddressAttribute>(
+      cricket::STUN_ATTR_XOR_RELAYED_ADDRESS,
+      external_socket_->GetLocalAddress());
+  auto lifetime_attr = std::make_unique<cricket::StunUInt32Attribute>(
+      cricket::STUN_ATTR_LIFETIME, lifetime.seconds());
   response.AddAttribute(std::move(mapped_addr_attr));
   response.AddAttribute(std::move(relayed_addr_attr));
   response.AddAttribute(std::move(lifetime_attr));
@@ -638,7 +648,8 @@
   SendResponse(&response);
 }
 
-void TurnServerAllocation::HandleRefreshRequest(const TurnMessage* msg) {
+void TurnServerAllocation::HandleRefreshRequest(
+    const cricket::TurnMessage* msg) {
   // Figure out the new lifetime.
   TimeDelta lifetime = ComputeLifetime(*msg);
 
@@ -650,21 +661,23 @@
                    << ": Refreshed allocation, lifetime=" << lifetime.seconds();
 
   // Send a success response with a LIFETIME attribute.
-  TurnMessage response(GetStunSuccessResponseTypeOrZero(*msg),
-                       msg->transaction_id());
+  cricket::TurnMessage response(GetStunSuccessResponseTypeOrZero(*msg),
+                                msg->transaction_id());
 
-  auto lifetime_attr = std::make_unique<StunUInt32Attribute>(
-      STUN_ATTR_LIFETIME, lifetime.seconds());
+  auto lifetime_attr = std::make_unique<cricket::StunUInt32Attribute>(
+      cricket::STUN_ATTR_LIFETIME, lifetime.seconds());
   response.AddAttribute(std::move(lifetime_attr));
 
   SendResponse(&response);
 }
 
-void TurnServerAllocation::HandleSendIndication(const TurnMessage* msg) {
+void TurnServerAllocation::HandleSendIndication(
+    const cricket::TurnMessage* msg) {
   // Check mandatory attributes.
-  const StunByteStringAttribute* data_attr = msg->GetByteString(STUN_ATTR_DATA);
-  const StunAddressAttribute* peer_attr =
-      msg->GetAddress(STUN_ATTR_XOR_PEER_ADDRESS);
+  const cricket::StunByteStringAttribute* data_attr =
+      msg->GetByteString(cricket::STUN_ATTR_DATA);
+  const cricket::StunAddressAttribute* peer_attr =
+      msg->GetAddress(cricket::STUN_ATTR_XOR_PEER_ADDRESS);
   if (!data_attr || !peer_attr) {
     RTC_LOG(LS_WARNING) << ToString() << ": Received invalid send indication";
     return;
@@ -683,11 +696,11 @@
 }
 
 void TurnServerAllocation::HandleCreatePermissionRequest(
-    const TurnMessage* msg) {
+    const cricket::TurnMessage* msg) {
   RTC_DCHECK_RUN_ON(server_->thread_);
   // Check mandatory attributes.
-  const StunAddressAttribute* peer_attr =
-      msg->GetAddress(STUN_ATTR_XOR_PEER_ADDRESS);
+  const cricket::StunAddressAttribute* peer_attr =
+      msg->GetAddress(cricket::STUN_ATTR_XOR_PEER_ADDRESS);
   if (!peer_attr) {
     SendBadRequestResponse(msg);
     return;
@@ -695,7 +708,8 @@
 
   if (server_->reject_private_addresses_ &&
       webrtc::IPIsPrivate(peer_attr->GetAddress().ipaddr())) {
-    SendErrorResponse(msg, STUN_ERROR_FORBIDDEN, STUN_ERROR_REASON_FORBIDDEN);
+    SendErrorResponse(msg, cricket::STUN_ERROR_FORBIDDEN,
+                      cricket::STUN_ERROR_REASON_FORBIDDEN);
     return;
   }
 
@@ -706,12 +720,13 @@
                    << peer_attr->GetAddress().ToSensitiveString();
 
   // Send a success response.
-  TurnMessage response(GetStunSuccessResponseTypeOrZero(*msg),
-                       msg->transaction_id());
+  cricket::TurnMessage response(GetStunSuccessResponseTypeOrZero(*msg),
+                                msg->transaction_id());
   SendResponse(&response);
 }
 
-void TurnServerAllocation::HandleChannelBindRequest(const TurnMessage* msg) {
+void TurnServerAllocation::HandleChannelBindRequest(
+    const cricket::TurnMessage* msg) {
   RTC_DCHECK_RUN_ON(server_->thread_);
   if (server_->reject_bind_requests_) {
     RTC_LOG(LS_ERROR) << "HandleChannelBindRequest: Rejecting bind requests";
@@ -720,10 +735,10 @@
   }
 
   // Check mandatory attributes.
-  const StunUInt32Attribute* channel_attr =
-      msg->GetUInt32(STUN_ATTR_CHANNEL_NUMBER);
-  const StunAddressAttribute* peer_attr =
-      msg->GetAddress(STUN_ATTR_XOR_PEER_ADDRESS);
+  const cricket::StunUInt32Attribute* channel_attr =
+      msg->GetUInt32(cricket::STUN_ATTR_CHANNEL_NUMBER);
+  const cricket::StunAddressAttribute* peer_attr =
+      msg->GetAddress(cricket::STUN_ATTR_XOR_PEER_ADDRESS);
   if (!channel_attr || !peer_attr) {
     SendBadRequestResponse(msg);
     return;
@@ -765,8 +780,8 @@
                    << ", peer=" << peer_attr->GetAddress().ToSensitiveString();
 
   // Send a success response.
-  TurnMessage response(GetStunSuccessResponseTypeOrZero(*msg),
-                       msg->transaction_id());
+  cricket::TurnMessage response(GetStunSuccessResponseTypeOrZero(*msg),
+                                msg->transaction_id());
   SendResponse(&response);
 }
 
@@ -795,16 +810,17 @@
     rtc::ByteBufferWriter buf;
     buf.WriteUInt16(channel->id);
     buf.WriteUInt16(static_cast<uint16_t>(packet.payload().size()));
-    buf.Write(webrtc::ArrayView<const uint8_t>(packet.payload()));
+    buf.Write(ArrayView<const uint8_t>(packet.payload()));
     server_->Send(&conn_, buf);
   } else if (!server_->enable_permission_checks_ ||
              HasPermission(packet.source_address().ipaddr())) {
     // No channel, but a permission exists. Send as a data indication.
-    TurnMessage msg(TURN_DATA_INDICATION);
-    msg.AddAttribute(std::make_unique<StunXorAddressAttribute>(
-        STUN_ATTR_XOR_PEER_ADDRESS, packet.source_address()));
-    msg.AddAttribute(std::make_unique<StunByteStringAttribute>(
-        STUN_ATTR_DATA, packet.payload().data(), packet.payload().size()));
+    cricket::TurnMessage msg(cricket::TURN_DATA_INDICATION);
+    msg.AddAttribute(std::make_unique<cricket::StunXorAddressAttribute>(
+        cricket::STUN_ATTR_XOR_PEER_ADDRESS, packet.source_address()));
+    msg.AddAttribute(std::make_unique<cricket::StunByteStringAttribute>(
+        cricket::STUN_ATTR_DATA, packet.payload().data(),
+        packet.payload().size()));
     server_->SendStun(&conn_, &msg);
   } else {
     RTC_LOG(LS_WARNING)
@@ -813,19 +829,21 @@
   }
 }
 
-TimeDelta TurnServerAllocation::ComputeLifetime(const TurnMessage& msg) {
-  if (const StunUInt32Attribute* attr = msg.GetUInt32(STUN_ATTR_LIFETIME)) {
+TimeDelta TurnServerAllocation::ComputeLifetime(
+    const cricket::TurnMessage& msg) {
+  if (const cricket::StunUInt32Attribute* attr =
+          msg.GetUInt32(cricket::STUN_ATTR_LIFETIME)) {
     return std::min(TimeDelta::Seconds(static_cast<int>(attr->value())),
                     kDefaultAllocationTimeout);
   }
   return kDefaultAllocationTimeout;
 }
 
-bool TurnServerAllocation::HasPermission(const webrtc::IPAddress& addr) {
+bool TurnServerAllocation::HasPermission(const IPAddress& addr) {
   return FindPermission(addr) != perms_.end();
 }
 
-void TurnServerAllocation::AddPermission(const webrtc::IPAddress& addr) {
+void TurnServerAllocation::AddPermission(const IPAddress& addr) {
   auto perm = FindPermission(addr);
   if (perm == perms_.end()) {
     perm = perms_.insert(perms_.end(), {.peer = addr});
@@ -838,7 +856,7 @@
 }
 
 TurnServerAllocation::PermissionList::iterator
-TurnServerAllocation::FindPermission(const webrtc::IPAddress& addr) {
+TurnServerAllocation::FindPermission(const IPAddress& addr) {
   return absl::c_find_if(perms_,
                          [&](const Permission& p) { return p.peer == addr; });
 }
@@ -850,22 +868,24 @@
 }
 
 TurnServerAllocation::ChannelList::iterator TurnServerAllocation::FindChannel(
-    const webrtc::SocketAddress& addr) {
+    const SocketAddress& addr) {
   return absl::c_find_if(channels_,
                          [&](const Channel& c) { return c.peer == addr; });
 }
 
-void TurnServerAllocation::SendResponse(TurnMessage* msg) {
+void TurnServerAllocation::SendResponse(cricket::TurnMessage* msg) {
   // Success responses always have M-I.
   msg->AddMessageIntegrity(key_);
   server_->SendStun(&conn_, msg);
 }
 
-void TurnServerAllocation::SendBadRequestResponse(const TurnMessage* req) {
-  SendErrorResponse(req, STUN_ERROR_BAD_REQUEST, STUN_ERROR_REASON_BAD_REQUEST);
+void TurnServerAllocation::SendBadRequestResponse(
+    const cricket::TurnMessage* req) {
+  SendErrorResponse(req, cricket::STUN_ERROR_BAD_REQUEST,
+                    cricket::STUN_ERROR_REASON_BAD_REQUEST);
 }
 
-void TurnServerAllocation::SendErrorResponse(const TurnMessage* req,
+void TurnServerAllocation::SendErrorResponse(const cricket::TurnMessage* req,
                                              int code,
                                              absl::string_view reason) {
   server_->SendErrorResponse(&conn_, req, code, reason);
@@ -873,7 +893,7 @@
 
 void TurnServerAllocation::SendExternal(const void* data,
                                         size_t size,
-                                        const webrtc::SocketAddress& peer) {
+                                        const SocketAddress& peer) {
   rtc::PacketOptions options;
   external_socket_->SendTo(data, size, peer, options);
 }
@@ -887,4 +907,4 @@
                            delay);
 }
 
-}  // namespace cricket
+}  // namespace webrtc
diff --git a/p2p/test/turn_server.h b/p2p/test/turn_server.h
index 6431bef..26d7d00 100644
--- a/p2p/test/turn_server.h
+++ b/p2p/test/turn_server.h
@@ -35,14 +35,16 @@
 class ByteBufferWriter;
 class PacketSocketFactory;
 }  // namespace rtc
-
 namespace cricket {
+class StunMessage;
+class TurnMessage;
+}  // namespace cricket
+
+namespace webrtc {
 
 constexpr int kMinTurnChannelNumber = 0x4000;
 constexpr int kMaxTurnChannelNumber = 0x7FFF;
 
-class StunMessage;
-class TurnMessage;
 class TurnServer;
 
 // The default server port for TURN, as specified in RFC5766.
@@ -52,19 +54,19 @@
 class TurnServerConnection {
  public:
   TurnServerConnection() : proto_(webrtc::PROTO_UDP), socket_(NULL) {}
-  TurnServerConnection(const webrtc::SocketAddress& src,
-                       webrtc::ProtocolType proto,
+  TurnServerConnection(const SocketAddress& src,
+                       ProtocolType proto,
                        rtc::AsyncPacketSocket* socket);
-  const webrtc::SocketAddress& src() const { return src_; }
+  const SocketAddress& src() const { return src_; }
   rtc::AsyncPacketSocket* socket() { return socket_; }
   bool operator==(const TurnServerConnection& t) const;
   bool operator<(const TurnServerConnection& t) const;
   std::string ToString() const;
 
  private:
-  webrtc::SocketAddress src_;
-  webrtc::SocketAddress dst_;
-  webrtc::ProtocolType proto_;
+  SocketAddress src_;
+  SocketAddress dst_;
+  ProtocolType proto_;
   rtc::AsyncPacketSocket* socket_;
 };
 
@@ -76,7 +78,7 @@
 class TurnServerAllocation final {
  public:
   TurnServerAllocation(TurnServer* server_,
-                       webrtc::TaskQueueBase* thread,
+                       TaskQueueBase* thread,
                        const TurnServerConnection& conn,
                        rtc::AsyncPacketSocket* server_socket,
                        absl::string_view key);
@@ -93,51 +95,49 @@
 
   std::string ToString() const;
 
-  void HandleTurnMessage(const TurnMessage* msg);
+  void HandleTurnMessage(const cricket::TurnMessage* msg);
   void HandleChannelData(rtc::ArrayView<const uint8_t> payload);
 
  private:
   struct Channel {
-    webrtc::ScopedTaskSafety pending_delete;
+    ScopedTaskSafety pending_delete;
     const uint16_t id;
-    const webrtc::SocketAddress peer;
+    const SocketAddress peer;
   };
   struct Permission {
-    webrtc::ScopedTaskSafety pending_delete;
-    webrtc::IPAddress peer;
+    ScopedTaskSafety pending_delete;
+    IPAddress peer;
   };
   using PermissionList = std::list<Permission>;
   using ChannelList = std::list<Channel>;
 
-  void PostDeleteSelf(webrtc::TimeDelta delay);
+  void PostDeleteSelf(TimeDelta delay);
 
-  void HandleAllocateRequest(const TurnMessage* msg);
-  void HandleRefreshRequest(const TurnMessage* msg);
-  void HandleSendIndication(const TurnMessage* msg);
-  void HandleCreatePermissionRequest(const TurnMessage* msg);
-  void HandleChannelBindRequest(const TurnMessage* msg);
+  void HandleAllocateRequest(const cricket::TurnMessage* msg);
+  void HandleRefreshRequest(const cricket::TurnMessage* msg);
+  void HandleSendIndication(const cricket::TurnMessage* msg);
+  void HandleCreatePermissionRequest(const cricket::TurnMessage* msg);
+  void HandleChannelBindRequest(const cricket::TurnMessage* msg);
 
   void OnExternalPacket(rtc::AsyncPacketSocket* socket,
                         const rtc::ReceivedPacket& packet);
 
-  static webrtc::TimeDelta ComputeLifetime(const TurnMessage& msg);
-  bool HasPermission(const webrtc::IPAddress& addr);
-  void AddPermission(const webrtc::IPAddress& addr);
-  PermissionList::iterator FindPermission(const webrtc::IPAddress& addr);
+  static TimeDelta ComputeLifetime(const cricket::TurnMessage& msg);
+  bool HasPermission(const IPAddress& addr);
+  void AddPermission(const IPAddress& addr);
+  PermissionList::iterator FindPermission(const IPAddress& addr);
   ChannelList::iterator FindChannel(int channel_id);
-  ChannelList::iterator FindChannel(const webrtc::SocketAddress& addr);
+  ChannelList::iterator FindChannel(const SocketAddress& addr);
 
-  void SendResponse(TurnMessage* msg);
-  void SendBadRequestResponse(const TurnMessage* req);
-  void SendErrorResponse(const TurnMessage* req,
+  void SendResponse(cricket::TurnMessage* msg);
+  void SendBadRequestResponse(const cricket::TurnMessage* req);
+  void SendErrorResponse(const cricket::TurnMessage* req,
                          int code,
                          absl::string_view reason);
-  void SendExternal(const void* data,
-                    size_t size,
-                    const webrtc::SocketAddress& peer);
+  void SendExternal(const void* data, size_t size, const SocketAddress& peer);
 
   TurnServer* const server_;
-  webrtc::TaskQueueBase* const thread_;
+  TaskQueueBase* const thread_;
   TurnServerConnection conn_;
   std::unique_ptr<rtc::AsyncPacketSocket> external_socket_;
   std::string key_;
@@ -146,7 +146,7 @@
   std::string last_nonce_;
   PermissionList perms_;
   ChannelList channels_;
-  webrtc::ScopedTaskSafety safety_;
+  ScopedTaskSafety safety_;
 };
 
 // An interface through which the MD5 credential hash can be retrieved.
@@ -164,14 +164,14 @@
 // An interface enables Turn Server to control redirection behavior.
 class TurnRedirectInterface {
  public:
-  virtual bool ShouldRedirect(const webrtc::SocketAddress& address,
-                              webrtc::SocketAddress* out) = 0;
+  virtual bool ShouldRedirect(const SocketAddress& address,
+                              SocketAddress* out) = 0;
   virtual ~TurnRedirectInterface() {}
 };
 
 class StunMessageObserver {
  public:
-  virtual void ReceivedMessage(const TurnMessage* msg) = 0;
+  virtual void ReceivedMessage(const cricket::TurnMessage* msg) = 0;
   virtual void ReceivedChannelData(rtc::ArrayView<const uint8_t> payload) = 0;
   virtual ~StunMessageObserver() {}
 };
@@ -185,7 +185,7 @@
   typedef std::map<TurnServerConnection, std::unique_ptr<TurnServerAllocation>>
       AllocationMap;
 
-  explicit TurnServer(webrtc::TaskQueueBase* thread);
+  explicit TurnServer(TaskQueueBase* thread);
   ~TurnServer() override;
 
   // Gets/sets the realm value to use for the server.
@@ -246,18 +246,17 @@
   }
 
   // Starts listening for packets from internal clients.
-  void AddInternalSocket(rtc::AsyncPacketSocket* socket,
-                         webrtc::ProtocolType proto);
+  void AddInternalSocket(rtc::AsyncPacketSocket* socket, ProtocolType proto);
   // Starts listening for the connections on this socket. When someone tries
   // to connect, the connection will be accepted and a new internal socket
   // will be added.
   void AddInternalServerSocket(
       rtc::Socket* socket,
-      webrtc::ProtocolType proto,
+      ProtocolType proto,
       std::unique_ptr<rtc::SSLAdapterFactory> ssl_adapter_factory = nullptr);
   // Specifies the factory to use for creating external sockets.
   void SetExternalSocketFactory(rtc::PacketSocketFactory* factory,
-                                const webrtc::SocketAddress& address);
+                                const SocketAddress& address);
   // For testing only.
   std::string SetTimestampForNextNonce(int64_t timestamp) {
     RTC_DCHECK_RUN_ON(thread_);
@@ -288,15 +287,17 @@
   void HandleStunMessage(TurnServerConnection* conn,
                          rtc::ArrayView<const uint8_t> payload)
       RTC_RUN_ON(thread_);
-  void HandleBindingRequest(TurnServerConnection* conn, const StunMessage* msg)
+  void HandleBindingRequest(TurnServerConnection* conn,
+                            const cricket::StunMessage* msg)
       RTC_RUN_ON(thread_);
   void HandleAllocateRequest(TurnServerConnection* conn,
-                             const TurnMessage* msg,
+                             const cricket::TurnMessage* msg,
                              absl::string_view key) RTC_RUN_ON(thread_);
 
-  bool GetKey(const StunMessage* msg, std::string* key) RTC_RUN_ON(thread_);
+  bool GetKey(const cricket::StunMessage* msg, std::string* key)
+      RTC_RUN_ON(thread_);
   bool CheckAuthorization(TurnServerConnection* conn,
-                          StunMessage* msg,
+                          cricket::StunMessage* msg,
                           absl::string_view key) RTC_RUN_ON(thread_);
   bool ValidateNonce(absl::string_view nonce) const RTC_RUN_ON(thread_);
 
@@ -308,38 +309,37 @@
       RTC_RUN_ON(thread_);
 
   void SendErrorResponse(TurnServerConnection* conn,
-                         const StunMessage* req,
+                         const cricket::StunMessage* req,
                          int code,
                          absl::string_view reason);
 
   void SendErrorResponseWithRealmAndNonce(TurnServerConnection* conn,
-                                          const StunMessage* req,
+                                          const cricket::StunMessage* req,
                                           int code,
                                           absl::string_view reason)
       RTC_RUN_ON(thread_);
 
   void SendErrorResponseWithAlternateServer(TurnServerConnection* conn,
-                                            const StunMessage* req,
-                                            const webrtc::SocketAddress& addr)
+                                            const cricket::StunMessage* req,
+                                            const SocketAddress& addr)
       RTC_RUN_ON(thread_);
 
-  void SendStun(TurnServerConnection* conn, StunMessage* msg);
+  void SendStun(TurnServerConnection* conn, cricket::StunMessage* msg);
   void Send(TurnServerConnection* conn, const rtc::ByteBufferWriter& buf);
 
   void DestroyAllocation(TurnServerAllocation* allocation) RTC_RUN_ON(thread_);
   void DestroyInternalSocket(rtc::AsyncPacketSocket* socket)
       RTC_RUN_ON(thread_);
 
-  typedef std::map<rtc::AsyncPacketSocket*, webrtc::ProtocolType>
-      InternalSocketMap;
+  typedef std::map<rtc::AsyncPacketSocket*, ProtocolType> InternalSocketMap;
   struct ServerSocketInfo {
-    webrtc::ProtocolType proto;
+    ProtocolType proto;
     // If non-null, used to wrap accepted sockets.
     std::unique_ptr<rtc::SSLAdapterFactory> ssl_adapter_factory;
   };
   typedef std::map<rtc::Socket*, ServerSocketInfo> ServerSocketMap;
 
-  webrtc::TaskQueueBase* const thread_;
+  TaskQueueBase* const thread_;
   const std::string nonce_key_;
   std::string realm_ RTC_GUARDED_BY(thread_);
   std::string software_ RTC_GUARDED_BY(thread_);
@@ -357,7 +357,7 @@
   ServerSocketMap server_listen_sockets_ RTC_GUARDED_BY(thread_);
   std::unique_ptr<rtc::PacketSocketFactory> external_socket_factory_
       RTC_GUARDED_BY(thread_);
-  webrtc::SocketAddress external_addr_ RTC_GUARDED_BY(thread_);
+  SocketAddress external_addr_ RTC_GUARDED_BY(thread_);
 
   AllocationMap allocations_ RTC_GUARDED_BY(thread_);
 
@@ -372,6 +372,20 @@
   friend class TurnServerAllocation;
 };
 
+}  //  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::kMaxTurnChannelNumber;
+using ::webrtc::kMinTurnChannelNumber;
+using ::webrtc::StunMessageObserver;
+using ::webrtc::TURN_SERVER_PORT;
+using ::webrtc::TurnAuthInterface;
+using ::webrtc::TurnRedirectInterface;
+using ::webrtc::TurnServer;
+using ::webrtc::TurnServerAllocation;
+using ::webrtc::TurnServerConnection;
 }  // namespace cricket
 
 #endif  // P2P_TEST_TURN_SERVER_H_
diff --git a/p2p/test/turn_server_unittest.cc b/p2p/test/turn_server_unittest.cc
index 38d1371..a90b9fd 100644
--- a/p2p/test/turn_server_unittest.cc
+++ b/p2p/test/turn_server_unittest.cc
@@ -23,7 +23,7 @@
 // NOTE: This is a work in progress. Currently this file only has tests for
 // TurnServerConnection, a primitive class used by TurnServer.
 
-namespace cricket {
+namespace webrtc {
 
 class TurnServerConnectionTest : public ::testing::Test {
  public:
@@ -52,11 +52,9 @@
 
 TEST_F(TurnServerConnectionTest, ComparisonOperators) {
   std::unique_ptr<rtc::AsyncPacketSocket> socket1(
-      socket_factory_.CreateUdpSocket(webrtc::SocketAddress("1.1.1.1", 1), 0,
-                                      0));
+      socket_factory_.CreateUdpSocket(SocketAddress("1.1.1.1", 1), 0, 0));
   std::unique_ptr<rtc::AsyncPacketSocket> socket2(
-      socket_factory_.CreateUdpSocket(webrtc::SocketAddress("2.2.2.2", 2), 0,
-                                      0));
+      socket_factory_.CreateUdpSocket(SocketAddress("2.2.2.2", 2), 0, 0));
   TurnServerConnection connection1(socket2->GetLocalAddress(), PROTO_UDP,
                                    socket1.get());
   TurnServerConnection connection2(socket2->GetLocalAddress(), PROTO_UDP,
@@ -70,4 +68,4 @@
   ExpectNotEqual(connection1, connection4);
 }
 
-}  // namespace cricket
+}  // namespace webrtc
diff --git a/pc/channel_unittest.cc b/pc/channel_unittest.cc
index 0399aa3..e480a03 100644
--- a/pc/channel_unittest.cc
+++ b/pc/channel_unittest.cc
@@ -222,10 +222,10 @@
 
       if (flags1 & RAW_PACKET_TRANSPORT) {
         fake_rtp_packet_transport1_.reset(
-            new rtc::FakePacketTransport("channel1_rtp"));
+            new webrtc::FakePacketTransport("channel1_rtp"));
         if (!(flags1 & RTCP_MUX)) {
           fake_rtcp_packet_transport1_.reset(
-              new rtc::FakePacketTransport("channel1_rtcp"));
+              new webrtc::FakePacketTransport("channel1_rtcp"));
         }
       } else {
         // Confirmed to work with KT_RSA and KT_ECDSA.
@@ -248,10 +248,10 @@
       // Based on flags, create fake DTLS or raw packet transports.
       if (flags2 & RAW_PACKET_TRANSPORT) {
         fake_rtp_packet_transport2_.reset(
-            new rtc::FakePacketTransport("channel2_rtp"));
+            new webrtc::FakePacketTransport("channel2_rtp"));
         if (!(flags2 & RTCP_MUX)) {
           fake_rtcp_packet_transport2_.reset(
-              new rtc::FakePacketTransport("channel2_rtcp"));
+              new webrtc::FakePacketTransport("channel2_rtcp"));
         }
       } else {
         // Confirmed to work with KT_RSA and KT_ECDSA.
@@ -1571,10 +1571,10 @@
   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<rtc::FakePacketTransport> fake_rtp_packet_transport1_;
-  std::unique_ptr<rtc::FakePacketTransport> fake_rtcp_packet_transport1_;
-  std::unique_ptr<rtc::FakePacketTransport> fake_rtp_packet_transport2_;
-  std::unique_ptr<rtc::FakePacketTransport> fake_rtcp_packet_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_;
+  std::unique_ptr<webrtc::FakePacketTransport> fake_rtcp_packet_transport2_;
   std::unique_ptr<webrtc::RtpTransportInternal> rtp_transport1_;
   std::unique_ptr<webrtc::RtpTransportInternal> rtp_transport2_;
   std::unique_ptr<webrtc::RtpTransportInternal> new_rtp_transport_;
diff --git a/pc/data_channel_integrationtest.cc b/pc/data_channel_integrationtest.cc
index 50e124c..92d27b3 100644
--- a/pc/data_channel_integrationtest.cc
+++ b/pc/data_channel_integrationtest.cc
@@ -1513,7 +1513,7 @@
           "192.0.2.1", 3478};
       static const rtc::SocketAddress turn_server_1_external_address{
           "192.0.3.1", 0};
-      cricket::TestTurnServer* turn_server_1 = CreateTurnServer(
+      TestTurnServer* turn_server_1 = CreateTurnServer(
           turn_server_1_internal_address, turn_server_1_external_address);
 
       // Bypass permission check on received packets so media can be sent before
diff --git a/pc/peer_connection_integrationtest.cc b/pc/peer_connection_integrationtest.cc
index 863cd35..d3a945b 100644
--- a/pc/peer_connection_integrationtest.cc
+++ b/pc/peer_connection_integrationtest.cc
@@ -1971,8 +1971,8 @@
   }
 
   void StartStunServer(const SocketAddress& server_address) {
-    stun_server_ = cricket::TestStunServer::Create(firewall(), server_address,
-                                                   *network_thread());
+    stun_server_ =
+        TestStunServer::Create(firewall(), server_address, *network_thread());
   }
 
   bool TestIPv6() {
@@ -2015,7 +2015,7 @@
 
  private:
   uint32_t port_allocator_flags_;
-  cricket::TestStunServer::StunServerPtr stun_server_;
+  TestStunServer::StunServerPtr stun_server_;
 };
 
 // Ensure FakeClockForTest is constructed first (see class for rationale).
@@ -2535,10 +2535,10 @@
   static const SocketAddress turn_server_1_external_address{"88.88.88.1", 0};
   static const SocketAddress turn_server_2_internal_address{"99.99.99.0", 3478};
   static const SocketAddress turn_server_2_external_address{"99.99.99.1", 0};
-  cricket::TestTurnServer* turn_server_1 = CreateTurnServer(
+  TestTurnServer* turn_server_1 = CreateTurnServer(
       turn_server_1_internal_address, turn_server_1_external_address);
 
-  cricket::TestTurnServer* turn_server_2 = CreateTurnServer(
+  TestTurnServer* turn_server_2 = CreateTurnServer(
       turn_server_2_internal_address, turn_server_2_external_address);
   // Bypass permission check on received packets so media can be sent before
   // the candidate is signaled.
diff --git a/pc/peer_connection_rampup_tests.cc b/pc/peer_connection_rampup_tests.cc
index 341d879..cda8dcb 100644
--- a/pc/peer_connection_rampup_tests.cc
+++ b/pc/peer_connection_rampup_tests.cc
@@ -252,13 +252,13 @@
                         const std::string& common_name = "test turn server") {
     rtc::Thread* thread = network_thread();
     rtc::SocketFactory* factory = &firewall_socket_server_;
-    std::unique_ptr<cricket::TestTurnServer> turn_server;
+    std::unique_ptr<TestTurnServer> turn_server;
     SendTask(network_thread(), [&] {
       static const SocketAddress turn_server_internal_address{
           kTurnInternalAddress, kTurnInternalPort};
       static const SocketAddress turn_server_external_address{
           kTurnExternalAddress, kTurnExternalPort};
-      turn_server = std::make_unique<cricket::TestTurnServer>(
+      turn_server = std::make_unique<TestTurnServer>(
           thread, factory, turn_server_internal_address,
           turn_server_external_address, type, true /*ignore_bad_certs=*/,
           common_name);
@@ -328,7 +328,7 @@
   Clock* const clock_;
   // The turn servers should be accessed & deleted on the network thread to
   // avoid a race with the socket read/write which occurs on the network thread.
-  std::vector<std::unique_ptr<cricket::TestTurnServer>> turn_servers_;
+  std::vector<std::unique_ptr<TestTurnServer>> turn_servers_;
   // `virtual_socket_server_` is used by `network_thread_` so it must be
   // destroyed later.
   // TODO(bugs.webrtc.org/7668): We would like to update the virtual network we
diff --git a/pc/rtp_transport_unittest.cc b/pc/rtp_transport_unittest.cc
index ef616bb..6b8b9d1 100644
--- a/pc/rtp_transport_unittest.cc
+++ b/pc/rtp_transport_unittest.cc
@@ -97,9 +97,9 @@
   RtpTransport transport(kMuxDisabled, ExplicitKeyValueConfig(""));
 
   SignalObserver observer(&transport);
-  rtc::FakePacketTransport fake_rtcp("fake_rtcp");
+  FakePacketTransport fake_rtcp("fake_rtcp");
   fake_rtcp.SetWritable(true);
-  rtc::FakePacketTransport fake_rtp("fake_rtp");
+  FakePacketTransport fake_rtp("fake_rtp");
   fake_rtp.SetWritable(true);
 
   transport.SetRtcpPacketTransport(&fake_rtcp);  // rtcp ready
@@ -111,9 +111,9 @@
 TEST(RtpTransportTest, SettingRtpAndRtcpSignalsReady) {
   RtpTransport transport(kMuxDisabled, ExplicitKeyValueConfig(""));
   SignalObserver observer(&transport);
-  rtc::FakePacketTransport fake_rtcp("fake_rtcp");
+  FakePacketTransport fake_rtcp("fake_rtcp");
   fake_rtcp.SetWritable(true);
-  rtc::FakePacketTransport fake_rtp("fake_rtp");
+  FakePacketTransport fake_rtp("fake_rtp");
   fake_rtp.SetWritable(true);
 
   transport.SetRtpPacketTransport(&fake_rtp);  // rtp ready
@@ -125,7 +125,7 @@
 TEST(RtpTransportTest, SettingRtpWithRtcpMuxEnabledSignalsReady) {
   RtpTransport transport(kMuxEnabled, ExplicitKeyValueConfig(""));
   SignalObserver observer(&transport);
-  rtc::FakePacketTransport fake_rtp("fake_rtp");
+  FakePacketTransport fake_rtp("fake_rtp");
   fake_rtp.SetWritable(true);
 
   transport.SetRtpPacketTransport(&fake_rtp);  // rtp ready
@@ -135,7 +135,7 @@
 TEST(RtpTransportTest, DisablingRtcpMuxSignalsNotReady) {
   RtpTransport transport(kMuxEnabled, ExplicitKeyValueConfig(""));
   SignalObserver observer(&transport);
-  rtc::FakePacketTransport fake_rtp("fake_rtp");
+  FakePacketTransport fake_rtp("fake_rtp");
   fake_rtp.SetWritable(true);
 
   transport.SetRtpPacketTransport(&fake_rtp);  // rtp ready
@@ -148,7 +148,7 @@
 TEST(RtpTransportTest, EnablingRtcpMuxSignalsReady) {
   RtpTransport transport(kMuxDisabled, ExplicitKeyValueConfig(""));
   SignalObserver observer(&transport);
-  rtc::FakePacketTransport fake_rtp("fake_rtp");
+  FakePacketTransport fake_rtp("fake_rtp");
   fake_rtp.SetWritable(true);
 
   transport.SetRtpPacketTransport(&fake_rtp);  // rtp ready
@@ -162,7 +162,7 @@
 TEST(RtpTransportTest, SetRtpTransportWithNetworkRouteChanged) {
   RtpTransport transport(kMuxDisabled, ExplicitKeyValueConfig(""));
   SignalObserver observer(&transport);
-  rtc::FakePacketTransport fake_rtp("fake_rtp");
+  FakePacketTransport fake_rtp("fake_rtp");
 
   EXPECT_FALSE(observer.network_route());
 
@@ -191,7 +191,7 @@
 TEST(RtpTransportTest, SetRtcpTransportWithNetworkRouteChanged) {
   RtpTransport transport(kMuxDisabled, ExplicitKeyValueConfig(""));
   SignalObserver observer(&transport);
-  rtc::FakePacketTransport fake_rtcp("fake_rtcp");
+  FakePacketTransport fake_rtcp("fake_rtcp");
 
   EXPECT_FALSE(observer.network_route());
 
@@ -223,8 +223,8 @@
   // If the RTCP-mux is not enabled, RTCP packets are expected to be sent over
   // the RtcpPacketTransport.
   RtpTransport transport(kMuxDisabled, ExplicitKeyValueConfig(""));
-  rtc::FakePacketTransport fake_rtcp("fake_rtcp");
-  rtc::FakePacketTransport fake_rtp("fake_rtp");
+  FakePacketTransport fake_rtcp("fake_rtcp");
+  FakePacketTransport fake_rtp("fake_rtp");
   transport.SetRtcpPacketTransport(&fake_rtcp);  // rtcp ready
   transport.SetRtpPacketTransport(&fake_rtp);    // rtp ready
   SignalObserver observer(&transport);
@@ -246,7 +246,7 @@
 TEST(RtpTransportTest, ChangingReadyToSendStateOnlySignalsWhenChanged) {
   RtpTransport transport(kMuxEnabled, ExplicitKeyValueConfig(""));
   TransportObserver observer(&transport);
-  rtc::FakePacketTransport fake_rtp("fake_rtp");
+  FakePacketTransport fake_rtp("fake_rtp");
   fake_rtp.SetWritable(true);
 
   // State changes, so we should signal.
@@ -270,7 +270,7 @@
 // received.
 TEST(RtpTransportTest, SignalDemuxedRtcp) {
   RtpTransport transport(kMuxDisabled, ExplicitKeyValueConfig(""));
-  rtc::FakePacketTransport fake_rtp("fake_rtp");
+  FakePacketTransport fake_rtp("fake_rtp");
   fake_rtp.SetDestination(&fake_rtp, true);
   transport.SetRtpPacketTransport(&fake_rtp);
   TransportObserver observer(&transport);
@@ -293,7 +293,7 @@
 // handled payload type is received.
 TEST(RtpTransportTest, SignalHandledRtpPayloadType) {
   RtpTransport transport(kMuxDisabled, ExplicitKeyValueConfig(""));
-  rtc::FakePacketTransport fake_rtp("fake_rtp");
+  FakePacketTransport fake_rtp("fake_rtp");
   fake_rtp.SetDestination(&fake_rtp, true);
   transport.SetRtpPacketTransport(&fake_rtp);
   TransportObserver observer(&transport);
@@ -317,7 +317,7 @@
 TEST(RtpTransportTest, ReceivedPacketEcnMarkingPropagatedToDemuxedPacket) {
   RtpTransport transport(kMuxDisabled, ExplicitKeyValueConfig(""));
   // Setup FakePacketTransport to send packets to itself.
-  rtc::FakePacketTransport fake_rtp("fake_rtp");
+  FakePacketTransport fake_rtp("fake_rtp");
   fake_rtp.SetDestination(&fake_rtp, true);
   transport.SetRtpPacketTransport(&fake_rtp);
   TransportObserver observer(&transport);
@@ -341,7 +341,7 @@
 // unhandled payload type is received.
 TEST(RtpTransportTest, DontSignalUnhandledRtpPayloadType) {
   RtpTransport transport(kMuxDisabled, ExplicitKeyValueConfig(""));
-  rtc::FakePacketTransport fake_rtp("fake_rtp");
+  FakePacketTransport fake_rtp("fake_rtp");
   fake_rtp.SetDestination(&fake_rtp, true);
   transport.SetRtpPacketTransport(&fake_rtp);
   TransportObserver observer(&transport);
@@ -367,7 +367,7 @@
   RtpTransport transport(kMuxEnabled, ExplicitKeyValueConfig(""));
   TransportObserver observer(&transport);
 
-  rtc::FakePacketTransport fake_rtp("fake_rtp");
+  FakePacketTransport fake_rtp("fake_rtp");
   fake_rtp.SetDestination(&fake_rtp, true);
   transport.SetRtpPacketTransport(&fake_rtp);
   fake_rtp.SetWritable(true);
@@ -391,7 +391,7 @@
   RtpTransport transport(
       kMuxEnabled,
       ExplicitKeyValueConfig("WebRTC-SetReadyToSendFalseIfSendFail/Enabled/"));
-  rtc::FakePacketTransport fake_rtp("fake_rtp");
+  FakePacketTransport fake_rtp("fake_rtp");
   transport.SetRtpPacketTransport(&fake_rtp);
   TransportObserver observer(&transport);
   observer.SetActionOnReadyToSend([&](bool ready) {
@@ -418,7 +418,7 @@
   const int kShortTimeout = 100;
   test::RunLoop loop;
   RtpTransport transport(kMuxDisabled, ExplicitKeyValueConfig(""));
-  rtc::FakePacketTransport fake_rtp("fake_rtp");
+  FakePacketTransport fake_rtp("fake_rtp");
   transport.SetRtpPacketTransport(&fake_rtp);
   fake_rtp.SetDestination(&fake_rtp, true);
   TransportObserver observer(&transport);
diff --git a/pc/slow_peer_connection_integration_test.cc b/pc/slow_peer_connection_integration_test.cc
index b6fc7a4..28a858f 100644
--- a/pc/slow_peer_connection_integration_test.cc
+++ b/pc/slow_peer_connection_integration_test.cc
@@ -280,8 +280,8 @@
   }
 
   void StartStunServer(const SocketAddress& server_address) {
-    stun_server_ = cricket::TestStunServer::Create(firewall(), server_address,
-                                                   *network_thread());
+    stun_server_ =
+        TestStunServer::Create(firewall(), server_address, *network_thread());
   }
 
   bool TestIPv6() {
@@ -324,7 +324,7 @@
 
  private:
   uint32_t port_allocator_flags_;
-  cricket::TestStunServer::StunServerPtr stun_server_;
+  TestStunServer::StunServerPtr stun_server_;
 };
 
 // Ensure FakeClockForTest is constructed first (see class for rationale).
@@ -341,7 +341,7 @@
 // to time out.
 TEST_P(PeerConnectionIntegrationIceStatesTestWithFakeClock, VerifyIceStates) {
   const SocketAddress kStunServerAddress =
-      SocketAddress("99.99.99.1", cricket::STUN_SERVER_PORT);
+      SocketAddress("99.99.99.1", STUN_SERVER_PORT);
   StartStunServer(kStunServerAddress);
 
   PeerConnectionInterface::RTCConfiguration config;
diff --git a/pc/srtp_transport_unittest.cc b/pc/srtp_transport_unittest.cc
index 890474c..a742fb9 100644
--- a/pc/srtp_transport_unittest.cc
+++ b/pc/srtp_transport_unittest.cc
@@ -55,9 +55,9 @@
     bool rtcp_mux_enabled = true;
 
     rtp_packet_transport1_ =
-        std::make_unique<rtc::FakePacketTransport>("fake_packet_transport1");
+        std::make_unique<FakePacketTransport>("fake_packet_transport1");
     rtp_packet_transport2_ =
-        std::make_unique<rtc::FakePacketTransport>("fake_packet_transport2");
+        std::make_unique<FakePacketTransport>("fake_packet_transport2");
 
     bool asymmetric = false;
     rtp_packet_transport1_->SetDestination(rtp_packet_transport2_.get(),
@@ -158,7 +158,7 @@
                           original_rtp_data, rtp_len));
       // Get the encrypted packet from underneath packet transport and verify
       // the data is actually encrypted.
-      auto fake_rtp_packet_transport = static_cast<rtc::FakePacketTransport*>(
+      auto fake_rtp_packet_transport = static_cast<FakePacketTransport*>(
           srtp_transport1_->rtp_packet_transport());
       EXPECT_NE(0, memcmp(fake_rtp_packet_transport->last_sent_packet()->data(),
                           original_rtp_data, rtp_len));
@@ -173,7 +173,7 @@
       ASSERT_TRUE(rtp_sink1_.last_recv_rtp_packet().data());
       EXPECT_EQ(0, memcmp(rtp_sink1_.last_recv_rtp_packet().data(),
                           original_rtp_data, rtp_len));
-      auto fake_rtp_packet_transport = static_cast<rtc::FakePacketTransport*>(
+      auto fake_rtp_packet_transport = static_cast<FakePacketTransport*>(
           srtp_transport2_->rtp_packet_transport());
       EXPECT_NE(0, memcmp(fake_rtp_packet_transport->last_sent_packet()->data(),
                           original_rtp_data, rtp_len));
@@ -202,7 +202,7 @@
                         rtcp_packet_data, rtcp_len));
     // Get the encrypted packet from underneath packet transport and verify the
     // data is actually encrypted.
-    auto fake_rtp_packet_transport = static_cast<rtc::FakePacketTransport*>(
+    auto fake_rtp_packet_transport = static_cast<FakePacketTransport*>(
         srtp_transport1_->rtp_packet_transport());
     EXPECT_NE(0, memcmp(fake_rtp_packet_transport->last_sent_packet()->data(),
                         rtcp_packet_data, rtcp_len));
@@ -213,7 +213,7 @@
     ASSERT_TRUE(rtp_sink1_.last_recv_rtcp_packet().data());
     EXPECT_EQ(0, memcmp(rtp_sink1_.last_recv_rtcp_packet().data(),
                         rtcp_packet_data, rtcp_len));
-    fake_rtp_packet_transport = static_cast<rtc::FakePacketTransport*>(
+    fake_rtp_packet_transport = static_cast<FakePacketTransport*>(
         srtp_transport2_->rtp_packet_transport());
     EXPECT_NE(0, memcmp(fake_rtp_packet_transport->last_sent_packet()->data(),
                         rtcp_packet_data, rtcp_len));
@@ -280,7 +280,7 @@
                         original_rtp_data, rtp_len));
     // Get the encrypted packet from underneath packet transport and verify the
     // data and header extension are actually encrypted.
-    auto fake_rtp_packet_transport = static_cast<rtc::FakePacketTransport*>(
+    auto fake_rtp_packet_transport = static_cast<FakePacketTransport*>(
         srtp_transport1_->rtp_packet_transport());
     EXPECT_NE(0, memcmp(fake_rtp_packet_transport->last_sent_packet()->data(),
                         original_rtp_data, rtp_len));
@@ -296,7 +296,7 @@
     ASSERT_TRUE(rtp_sink1_.last_recv_rtp_packet().data());
     EXPECT_EQ(0, memcmp(rtp_sink1_.last_recv_rtp_packet().data(),
                         original_rtp_data, rtp_len));
-    fake_rtp_packet_transport = static_cast<rtc::FakePacketTransport*>(
+    fake_rtp_packet_transport = static_cast<FakePacketTransport*>(
         srtp_transport2_->rtp_packet_transport());
     EXPECT_NE(0, memcmp(fake_rtp_packet_transport->last_sent_packet()->data(),
                         original_rtp_data, rtp_len));
@@ -333,8 +333,8 @@
   std::unique_ptr<SrtpTransport> srtp_transport1_;
   std::unique_ptr<SrtpTransport> srtp_transport2_;
 
-  std::unique_ptr<rtc::FakePacketTransport> rtp_packet_transport1_;
-  std::unique_ptr<rtc::FakePacketTransport> rtp_packet_transport2_;
+  std::unique_ptr<FakePacketTransport> rtp_packet_transport1_;
+  std::unique_ptr<FakePacketTransport> rtp_packet_transport2_;
 
   TransportObserver rtp_sink1_;
   TransportObserver rtp_sink2_;
@@ -426,8 +426,8 @@
       "WebRTC-SrtpRemoveReceiveStream/Enabled/");
   auto srtp_transport =
       std::make_unique<SrtpTransport>(/*rtcp_mux_enabled=*/true, field_trials);
-  auto rtp_packet_transport = std::make_unique<rtc::FakePacketTransport>(
-      "fake_packet_transport_loopback");
+  auto rtp_packet_transport =
+      std::make_unique<FakePacketTransport>("fake_packet_transport_loopback");
 
   bool asymmetric = false;
   rtp_packet_transport->SetDestination(rtp_packet_transport.get(), asymmetric);
diff --git a/pc/test/integration_test_helpers.h b/pc/test/integration_test_helpers.h
index fb2bf9a..b2d2e41 100644
--- a/pc/test/integration_test_helpers.h
+++ b/pc/test/integration_test_helpers.h
@@ -1635,16 +1635,16 @@
     return caller_ && callee_;
   }
 
-  cricket::TestTurnServer* CreateTurnServer(
+  TestTurnServer* CreateTurnServer(
       SocketAddress internal_address,
       SocketAddress external_address,
       ProtocolType type = ProtocolType::PROTO_UDP,
       const std::string& common_name = "test turn server") {
     rtc::Thread* thread = network_thread();
     rtc::SocketFactory* socket_factory = fss_.get();
-    std::unique_ptr<cricket::TestTurnServer> turn_server;
+    std::unique_ptr<TestTurnServer> turn_server;
     SendTask(network_thread(), [&] {
-      turn_server = std::make_unique<cricket::TestTurnServer>(
+      turn_server = std::make_unique<TestTurnServer>(
           thread, socket_factory, internal_address, external_address, type,
           /*ignore_bad_certs=*/true, common_name);
     });
@@ -1653,11 +1653,10 @@
     return turn_servers_.back().get();
   }
 
-  cricket::TestTurnCustomizer* CreateTurnCustomizer() {
-    std::unique_ptr<cricket::TestTurnCustomizer> turn_customizer;
-    SendTask(network_thread(), [&] {
-      turn_customizer = std::make_unique<cricket::TestTurnCustomizer>();
-    });
+  TestTurnCustomizer* CreateTurnCustomizer() {
+    std::unique_ptr<TestTurnCustomizer> turn_customizer;
+    SendTask(network_thread(),
+             [&] { turn_customizer = std::make_unique<TestTurnCustomizer>(); });
     turn_customizers_.push_back(std::move(turn_customizer));
     // Interactions with the turn customizer should be done on the network
     // thread.
@@ -1667,7 +1666,7 @@
   // Checks that the function counters for a TestTurnCustomizer are greater than
   // 0.
   void ExpectTurnCustomizerCountersIncremented(
-      cricket::TestTurnCustomizer* turn_customizer) {
+      TestTurnCustomizer* turn_customizer) {
     SendTask(network_thread(), [turn_customizer] {
       EXPECT_GT(turn_customizer->allow_channel_data_cnt_, 0u);
       EXPECT_GT(turn_customizer->modify_cnt_, 0u);
@@ -1922,8 +1921,8 @@
   // The turn servers and turn customizers should be accessed & deleted on the
   // network thread to avoid a race with the socket read/write that occurs
   // on the network thread.
-  std::vector<std::unique_ptr<cricket::TestTurnServer>> turn_servers_;
-  std::vector<std::unique_ptr<cricket::TestTurnCustomizer>> turn_customizers_;
+  std::vector<std::unique_ptr<TestTurnServer>> turn_servers_;
+  std::vector<std::unique_ptr<TestTurnCustomizer>> turn_customizers_;
   std::unique_ptr<PeerConnectionIntegrationWrapper> caller_;
   std::unique_ptr<PeerConnectionIntegrationWrapper> callee_;
   std::string field_trials_;
diff --git a/rtc_base/ssl_identity.h b/rtc_base/ssl_identity.h
index 46b36de..96462df 100644
--- a/rtc_base/ssl_identity.h
+++ b/rtc_base/ssl_identity.h
@@ -55,7 +55,7 @@
 class RTC_EXPORT KeyParams {
  public:
   // Generate a KeyParams object from a simple KeyType, using default params.
-  explicit KeyParams(KeyType key_type = KT_DEFAULT);
+  explicit KeyParams(KeyType key_type = rtc::KT_DEFAULT);
 
   // Generate a a KeyParams for RSA with explicit parameters.
   static KeyParams RSA(int mod_size = rtc::kRsaDefaultModSize,
diff --git a/test/network/emulated_turn_server.cc b/test/network/emulated_turn_server.cc
index 49b29e4..b4ae8f2 100644
--- a/test/network/emulated_turn_server.cc
+++ b/test/network/emulated_turn_server.cc
@@ -141,7 +141,7 @@
   SendTask(thread_.get(), [this, enable_permission_checks =
                                      config.enable_permission_checks]() {
     RTC_DCHECK_RUN_ON(thread_.get());
-    turn_server_ = std::make_unique<cricket::TurnServer>(thread_.get());
+    turn_server_ = std::make_unique<TurnServer>(thread_.get());
     turn_server_->set_realm(kTestRealm);
     turn_server_->set_realm(kTestSoftware);
     turn_server_->set_auth_hook(this);
diff --git a/test/network/emulated_turn_server.h b/test/network/emulated_turn_server.h
index fed93aa..eedd86b 100644
--- a/test/network/emulated_turn_server.h
+++ b/test/network/emulated_turn_server.h
@@ -40,7 +40,7 @@
 // using a wrapper around AsyncPacketSocket (no lookup required as the
 // wrapper around AsyncPacketSocket keep a pointer to the EmulatedEndpoint).
 class EmulatedTURNServer : public EmulatedTURNServerInterface,
-                           public cricket::TurnAuthInterface,
+                           public TurnAuthInterface,
                            public webrtc::EmulatedNetworkReceiverInterface {
  public:
   // Create an EmulatedTURNServer.
@@ -88,7 +88,7 @@
   IceServerConfig ice_config_;
   EmulatedEndpoint* const client_;
   EmulatedEndpoint* const peer_;
-  std::unique_ptr<cricket::TurnServer> turn_server_ RTC_GUARDED_BY(&thread_);
+  std::unique_ptr<TurnServer> turn_server_ RTC_GUARDED_BY(&thread_);
   class AsyncPacketSocketWrapper;
   std::map<SocketAddress, AsyncPacketSocketWrapper*> sockets_
       RTC_GUARDED_BY(&thread_);