Add checks for api/test mocks to make sure they're complete

Also unifies the mock inheritance if they inherited from a ref counted
interface:
 - it should only inherit from the interface
 - it should use make_ref_counted

Bug: webrtc:14594
Change-Id: I7b0514b632ccd0798028b50f19812ac0a196e13c
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/262423
Commit-Queue: Florent Castelli <orphis@webrtc.org>
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#38602}
diff --git a/api/BUILD.gn b/api/BUILD.gn
index de839ad..7e78edd 100644
--- a/api/BUILD.gn
+++ b/api/BUILD.gn
@@ -978,6 +978,7 @@
     sources = [ "test/mock_audio_mixer.h" ]
 
     deps = [
+      ":make_ref_counted",
       "../test:test_support",
       "audio:audio_mixer_api",
     ]
@@ -989,7 +990,7 @@
     sources = [ "test/mock_audio_sink.h" ]
 
     deps = [
-      "../api:media_stream_interface",
+      ":media_stream_interface",
       "../test:test_support",
     ]
     absl_deps = [ "//third_party/abseil-cpp/absl/types:optional" ]
@@ -1002,6 +1003,7 @@
 
     deps = [
       ":libjingle_peerconnection_api",
+      ":make_ref_counted",
       "../test:test_support",
     ]
   }
@@ -1013,6 +1015,7 @@
 
     deps = [
       ":libjingle_peerconnection_api",
+      ":make_ref_counted",
       "../test:test_support",
     ]
   }
@@ -1032,8 +1035,7 @@
     testonly = true
     sources = [ "test/mock_frame_encryptor.h" ]
     deps = [
-      # For api/crypto/frame_encryptor_interface.h
-      ":libjingle_peerconnection_api",
+      ":make_ref_counted",
       "../test:test_support",
       "crypto:frame_encryptor_interface",
     ]
@@ -1044,7 +1046,7 @@
     testonly = true
     sources = [ "test/mock_frame_decryptor.h" ]
     deps = [
-      ":libjingle_peerconnection_api",
+      ":make_ref_counted",
       "../test:test_support",
       "crypto:frame_decryptor_interface",
     ]
@@ -1055,9 +1057,8 @@
     testonly = true
     sources = [ "test/mock_encoder_selector.h" ]
     deps = [
-      ":libjingle_peerconnection_api",
-      "../api/video_codecs:video_codecs_api",
       "../test:test_support",
+      "video_codecs:video_codecs_api",
     ]
   }
 
@@ -1070,8 +1071,6 @@
     ]
     deps = [
       ":array_view",
-      ":libjingle_peerconnection_api",
-      ":make_ref_counted",
       ":rtp_parameters",
       "../rtc_base:checks",
       "../rtc_base:refcount",
@@ -1088,8 +1087,6 @@
     ]
     deps = [
       ":array_view",
-      ":libjingle_peerconnection_api",
-      ":make_ref_counted",
       ":rtp_parameters",
       "../rtc_base:checks",
       "crypto:frame_decryptor_interface",
@@ -1102,6 +1099,7 @@
     sources = [ "test/mock_media_stream_interface.h" ]
 
     deps = [
+      ":make_ref_counted",
       ":media_stream_interface",
       "../test:test_support",
     ]
@@ -1125,8 +1123,8 @@
 
     deps = [
       ":libjingle_peerconnection_api",
-      "../api:scoped_refptr",
-      "../rtc_base:refcount",
+      ":make_ref_counted",
+      ":scoped_refptr",
       "../test:test_support",
     ]
   }
@@ -1138,6 +1136,7 @@
 
     deps = [
       ":libjingle_peerconnection_api",
+      ":make_ref_counted",
       "../test:test_support",
     ]
   }
@@ -1173,6 +1172,7 @@
 
     deps = [
       ":libjingle_peerconnection_api",
+      ":make_ref_counted",
       "../test:test_support",
     ]
   }
@@ -1194,8 +1194,8 @@
     sources = [ "test/mock_video_bitrate_allocator.h" ]
 
     deps = [
-      "../api/video:video_bitrate_allocator",
       "../test:test_support",
+      "video:video_bitrate_allocator",
     ]
   }
 
@@ -1205,8 +1205,8 @@
     sources = [ "test/mock_video_bitrate_allocator_factory.h" ]
 
     deps = [
-      "../api/video:video_bitrate_allocator_factory",
       "../test:test_support",
+      "video:video_bitrate_allocator_factory",
     ]
   }
 
@@ -1219,8 +1219,8 @@
     ]
 
     deps = [
-      "../api/video_codecs:video_codecs_api",
       "../test:test_support",
+      "video_codecs:video_codecs_api",
     ]
   }
 
@@ -1230,8 +1230,8 @@
     sources = [ "test/mock_video_decoder.h" ]
 
     deps = [
-      "../api/video_codecs:video_codecs_api",
       "../test:test_support",
+      "video_codecs:video_codecs_api",
     ]
   }
 
@@ -1241,8 +1241,8 @@
     sources = [ "test/mock_video_encoder.h" ]
 
     deps = [
-      "../api/video_codecs:video_codecs_api",
       "../test:test_support",
+      "video_codecs:video_codecs_api",
     ]
   }
 
@@ -1252,9 +1252,9 @@
     sources = [ "test/mock_video_track.h" ]
 
     deps = [
-      "../api:media_stream_interface",
-      "../api:scoped_refptr",
-      "../rtc_base:refcount",
+      ":make_ref_counted",
+      ":media_stream_interface",
+      ":scoped_refptr",
       "../test:test_support",
     ]
   }
diff --git a/api/DEPS b/api/DEPS
index 5f01204..484588e 100644
--- a/api/DEPS
+++ b/api/DEPS
@@ -250,14 +250,6 @@
     "+test/gmock.h",
   ],
 
-  "mock_peerconnectioninterface\.h": [
-    "+rtc_base/ref_counted_object.h",
-  ],
-
-  "mock_video_track\.h": [
-    "+rtc_base/ref_counted_object.h",
-  ],
-
   "notifier\.h": [
     "+rtc_base/system/no_unique_address.h",
   ],
diff --git a/api/task_queue/test/mock_task_queue_base.h b/api/task_queue/test/mock_task_queue_base.h
index 2e99be7..4b73d8f 100644
--- a/api/task_queue/test/mock_task_queue_base.h
+++ b/api/task_queue/test/mock_task_queue_base.h
@@ -32,6 +32,8 @@
               (override));
 };
 
+static_assert(!std::is_abstract_v<MockTaskQueueBase>);
+
 }  // namespace webrtc
 
 #endif  // API_TASK_QUEUE_TEST_MOCK_TASK_QUEUE_BASE_H_
diff --git a/api/test/mock_async_dns_resolver.h b/api/test/mock_async_dns_resolver.h
index 81132c9..c5048c8 100644
--- a/api/test/mock_async_dns_resolver.h
+++ b/api/test/mock_async_dns_resolver.h
@@ -28,6 +28,8 @@
   MOCK_METHOD(int, GetError, (), (const, override));
 };
 
+static_assert(!std::is_abstract_v<MockAsyncDnsResolverResult>);
+
 class MockAsyncDnsResolver : public AsyncDnsResolverInterface {
  public:
   MOCK_METHOD(void,
@@ -41,6 +43,8 @@
   MOCK_METHOD(AsyncDnsResolverResult&, result, (), (const, override));
 };
 
+static_assert(!std::is_abstract_v<MockAsyncDnsResolver>);
+
 class MockAsyncDnsResolverFactory : public AsyncDnsResolverFactoryInterface {
  public:
   MOCK_METHOD(std::unique_ptr<webrtc::AsyncDnsResolverInterface>,
@@ -57,6 +61,8 @@
               (override));
 };
 
+static_assert(!std::is_abstract_v<MockAsyncDnsResolverFactory>);
+
 }  // namespace webrtc
 
 #endif  // API_TEST_MOCK_ASYNC_DNS_RESOLVER_H_
diff --git a/api/test/mock_audio_mixer.h b/api/test/mock_audio_mixer.h
index 88dc108..8747356 100644
--- a/api/test/mock_audio_mixer.h
+++ b/api/test/mock_audio_mixer.h
@@ -12,6 +12,7 @@
 #define API_TEST_MOCK_AUDIO_MIXER_H_
 
 #include "api/audio/audio_mixer.h"
+#include "api/make_ref_counted.h"
 #include "test/gmock.h"
 
 namespace webrtc {
@@ -19,10 +20,20 @@
 
 class MockAudioMixer : public AudioMixer {
  public:
+  static rtc::scoped_refptr<MockAudioMixer> Create() {
+    return rtc::make_ref_counted<MockAudioMixer>();
+  }
+
   MOCK_METHOD(bool, AddSource, (Source*), (override));
   MOCK_METHOD(void, RemoveSource, (Source*), (override));
   MOCK_METHOD(void, Mix, (size_t number_of_channels, AudioFrame*), (override));
+
+ protected:
+  MockAudioMixer() = default;
 };
+
+static_assert(!std::is_abstract_v<rtc::RefCountedObject<MockAudioMixer>>);
+
 }  // namespace test
 }  // namespace webrtc
 
diff --git a/api/test/mock_audio_sink.h b/api/test/mock_audio_sink.h
index 0c17dc4..ae8c856 100644
--- a/api/test/mock_audio_sink.h
+++ b/api/test/mock_audio_sink.h
@@ -39,6 +39,8 @@
               (override));
 };
 
+static_assert(!std::is_abstract_v<MockAudioSink>);
+
 }  // namespace webrtc
 
 #endif  // API_TEST_MOCK_AUDIO_SINK_H_
diff --git a/api/test/mock_data_channel.h b/api/test/mock_data_channel.h
index 40f7edb..afdf05b 100644
--- a/api/test/mock_data_channel.h
+++ b/api/test/mock_data_channel.h
@@ -14,16 +14,15 @@
 #include <string>
 
 #include "api/data_channel_interface.h"
+#include "api/make_ref_counted.h"
 #include "test/gmock.h"
 
 namespace webrtc {
 
-class MockDataChannelInterface final
-    : public rtc::RefCountedObject<webrtc::DataChannelInterface> {
+class MockDataChannelInterface : public webrtc::DataChannelInterface {
  public:
   static rtc::scoped_refptr<MockDataChannelInterface> Create() {
-    return rtc::scoped_refptr<MockDataChannelInterface>(
-        new MockDataChannelInterface());
+    return rtc::make_ref_counted<MockDataChannelInterface>();
   }
 
   MOCK_METHOD(void,
@@ -56,6 +55,9 @@
   MockDataChannelInterface() = default;
 };
 
+static_assert(
+    !std::is_abstract_v<rtc::RefCountedObject<MockDataChannelInterface>>);
+
 }  // namespace webrtc
 
 #endif  // API_TEST_MOCK_DATA_CHANNEL_H_
diff --git a/api/test/mock_dtmf_sender.h b/api/test/mock_dtmf_sender.h
index 9029195..78ae475 100644
--- a/api/test/mock_dtmf_sender.h
+++ b/api/test/mock_dtmf_sender.h
@@ -14,6 +14,7 @@
 #include <string>
 
 #include "api/dtmf_sender_interface.h"
+#include "api/make_ref_counted.h"
 #include "test/gmock.h"
 
 namespace webrtc {
@@ -27,7 +28,7 @@
   MOCK_METHOD(void, OnToneChange, (const std::string&), (override));
 };
 
-static_assert(!std::is_abstract_v<MockDtmfSenderObserver>, "");
+static_assert(!std::is_abstract_v<MockDtmfSenderObserver>);
 
 class MockDtmfSender : public DtmfSenderInterface {
  public:
@@ -49,7 +50,7 @@
   MockDtmfSender() = default;
 };
 
-static_assert(!std::is_abstract_v<rtc::RefCountedObject<MockDtmfSender>>, "");
+static_assert(!std::is_abstract_v<rtc::RefCountedObject<MockDtmfSender>>);
 
 }  // namespace webrtc
 
diff --git a/api/test/mock_fec_controller_override.h b/api/test/mock_fec_controller_override.h
index 8f3accb..4fff228 100644
--- a/api/test/mock_fec_controller_override.h
+++ b/api/test/mock_fec_controller_override.h
@@ -21,6 +21,8 @@
   MOCK_METHOD(void, SetFecAllowed, (bool fec_allowed), (override));
 };
 
+static_assert(!std::is_abstract_v<MockFecControllerOverride>);
+
 }  // namespace webrtc
 
 #endif  // API_TEST_MOCK_FEC_CONTROLLER_OVERRIDE_H_
diff --git a/api/test/mock_frame_decryptor.h b/api/test/mock_frame_decryptor.h
index 9604b96..c4320a4 100644
--- a/api/test/mock_frame_decryptor.h
+++ b/api/test/mock_frame_decryptor.h
@@ -14,12 +14,17 @@
 #include <vector>
 
 #include "api/crypto/frame_decryptor_interface.h"
+#include "api/make_ref_counted.h"
 #include "test/gmock.h"
 
 namespace webrtc {
 
 class MockFrameDecryptor : public FrameDecryptorInterface {
  public:
+  static rtc::scoped_refptr<MockFrameDecryptor> Create() {
+    return rtc::make_ref_counted<MockFrameDecryptor>();
+  }
+
   MOCK_METHOD(Result,
               Decrypt,
               (cricket::MediaType,
@@ -33,8 +38,13 @@
               GetMaxPlaintextByteSize,
               (cricket::MediaType, size_t encrypted_frame_size),
               (override));
+
+ protected:
+  MockFrameDecryptor() = default;
 };
 
+static_assert(!std::is_abstract_v<rtc::RefCountedObject<MockFrameDecryptor>>);
+
 }  // namespace webrtc
 
 #endif  // API_TEST_MOCK_FRAME_DECRYPTOR_H_
diff --git a/api/test/mock_frame_encryptor.h b/api/test/mock_frame_encryptor.h
index e47321f..cb20f62f 100644
--- a/api/test/mock_frame_encryptor.h
+++ b/api/test/mock_frame_encryptor.h
@@ -12,12 +12,17 @@
 #define API_TEST_MOCK_FRAME_ENCRYPTOR_H_
 
 #include "api/crypto/frame_encryptor_interface.h"
+#include "api/make_ref_counted.h"
 #include "test/gmock.h"
 
 namespace webrtc {
 
 class MockFrameEncryptor : public FrameEncryptorInterface {
  public:
+  static rtc::scoped_refptr<MockFrameEncryptor> Create() {
+    return rtc::make_ref_counted<MockFrameEncryptor>();
+  }
+
   MOCK_METHOD(int,
               Encrypt,
               (cricket::MediaType,
@@ -32,8 +37,13 @@
               GetMaxCiphertextByteSize,
               (cricket::MediaType media_type, size_t frame_size),
               (override));
+
+ protected:
+  MockFrameEncryptor() = default;
 };
 
+static_assert(!std::is_abstract_v<rtc::RefCountedObject<MockFrameEncryptor>>);
+
 }  // namespace webrtc
 
 #endif  // API_TEST_MOCK_FRAME_ENCRYPTOR_H_
diff --git a/api/test/mock_media_stream_interface.h b/api/test/mock_media_stream_interface.h
index 2099623..6baf02f 100644
--- a/api/test/mock_media_stream_interface.h
+++ b/api/test/mock_media_stream_interface.h
@@ -13,16 +13,16 @@
 
 #include <string>
 
+#include "api/make_ref_counted.h"
 #include "api/media_stream_interface.h"
 #include "test/gmock.h"
 
 namespace webrtc {
 
-class MockAudioSource final
-    : public rtc::RefCountedObject<AudioSourceInterface> {
+class MockAudioSource : public AudioSourceInterface {
  public:
   static rtc::scoped_refptr<MockAudioSource> Create() {
-    return rtc::scoped_refptr<MockAudioSource>(new MockAudioSource());
+    return rtc::make_ref_counted<MockAudioSource>();
   }
 
   MOCK_METHOD(void,
@@ -48,14 +48,16 @@
   MOCK_METHOD(void, RemoveSink, (AudioTrackSinkInterface * sink), (override));
   MOCK_METHOD(const cricket::AudioOptions, options, (), (const, override));
 
- private:
+ protected:
   MockAudioSource() = default;
 };
 
-class MockAudioTrack final : public rtc::RefCountedObject<AudioTrackInterface> {
+static_assert(!std::is_abstract_v<rtc::RefCountedObject<MockAudioSource>>);
+
+class MockAudioTrack : public AudioTrackInterface {
  public:
   static rtc::scoped_refptr<MockAudioTrack> Create() {
-    return rtc::scoped_refptr<MockAudioTrack>(new MockAudioTrack());
+    return rtc::make_ref_counted<MockAudioTrack>();
   }
 
   MOCK_METHOD(void,
@@ -80,12 +82,18 @@
               (),
               (override));
 
- private:
+ protected:
   MockAudioTrack() = default;
 };
 
+static_assert(!std::is_abstract_v<rtc::RefCountedObject<MockAudioTrack>>);
+
 class MockMediaStream : public MediaStreamInterface {
  public:
+  static rtc::scoped_refptr<MockMediaStream> Create() {
+    return rtc::make_ref_counted<MockMediaStream>();
+  }
+
   MOCK_METHOD(std::string, id, (), (const override));
   MOCK_METHOD(AudioTrackVector, GetAudioTracks, (), (override));
   MOCK_METHOD(VideoTrackVector, GetVideoTracks, (), (override));
@@ -128,7 +136,7 @@
               (override));
 };
 
-static_assert(!std::is_abstract_v<rtc::RefCountedObject<MockMediaStream>>, "");
+static_assert(!std::is_abstract_v<rtc::RefCountedObject<MockMediaStream>>);
 
 }  // namespace webrtc
 
diff --git a/api/test/mock_peer_connection_factory_interface.h b/api/test/mock_peer_connection_factory_interface.h
index 6bab595..5ba2c83 100644
--- a/api/test/mock_peer_connection_factory_interface.h
+++ b/api/test/mock_peer_connection_factory_interface.h
@@ -14,17 +14,17 @@
 #include <memory>
 #include <string>
 
+#include "api/make_ref_counted.h"
 #include "api/peer_connection_interface.h"
 #include "test/gmock.h"
 
 namespace webrtc {
 
-class MockPeerConnectionFactoryInterface final
-    : public rtc::RefCountedObject<webrtc::PeerConnectionFactoryInterface> {
+class MockPeerConnectionFactoryInterface
+    : public PeerConnectionFactoryInterface {
  public:
   static rtc::scoped_refptr<MockPeerConnectionFactoryInterface> Create() {
-    return rtc::scoped_refptr<MockPeerConnectionFactoryInterface>(
-        new MockPeerConnectionFactoryInterface());
+    return rtc::make_ref_counted<MockPeerConnectionFactoryInterface>();
   }
 
   MOCK_METHOD(void, SetOptions, (const Options&), (override));
@@ -76,6 +76,9 @@
   MockPeerConnectionFactoryInterface() = default;
 };
 
+static_assert(!std::is_abstract_v<
+              rtc::RefCountedObject<MockPeerConnectionFactoryInterface>>);
+
 }  // namespace webrtc
 
 #endif  // API_TEST_MOCK_PEER_CONNECTION_FACTORY_INTERFACE_H_
diff --git a/api/test/mock_peerconnectioninterface.h b/api/test/mock_peerconnectioninterface.h
index ccc6ce4..b779f19 100644
--- a/api/test/mock_peerconnectioninterface.h
+++ b/api/test/mock_peerconnectioninterface.h
@@ -17,10 +17,10 @@
 #include <utility>
 #include <vector>
 
+#include "api/make_ref_counted.h"
 #include "api/peer_connection_interface.h"
 #include "api/scoped_refptr.h"
 #include "api/sctp_transport_interface.h"
-#include "rtc_base/ref_counted_object.h"
 #include "test/gmock.h"
 
 namespace webrtc {
@@ -205,8 +205,7 @@
 };
 
 static_assert(
-    !std::is_abstract_v<rtc::RefCountedObject<MockPeerConnectionInterface>>,
-    "");
+    !std::is_abstract_v<rtc::RefCountedObject<MockPeerConnectionInterface>>);
 
 }  // namespace webrtc
 
diff --git a/api/test/mock_rtp_transceiver.h b/api/test/mock_rtp_transceiver.h
index 1d21bce..39c8773 100644
--- a/api/test/mock_rtp_transceiver.h
+++ b/api/test/mock_rtp_transceiver.h
@@ -14,6 +14,7 @@
 #include <string>
 #include <vector>
 
+#include "api/make_ref_counted.h"
 #include "api/rtp_transceiver_interface.h"
 #include "test/gmock.h"
 
@@ -21,8 +22,6 @@
 
 class MockRtpTransceiver : public RtpTransceiverInterface {
  public:
-  MockRtpTransceiver() = default;
-
   static rtc::scoped_refptr<MockRtpTransceiver> Create() {
     return rtc::make_ref_counted<MockRtpTransceiver>();
   }
@@ -80,8 +79,13 @@
               (rtc::ArrayView<const RtpHeaderExtensionCapability>
                    header_extensions_to_offer),
               (override));
+
+ protected:
+  MockRtpTransceiver() = default;
 };
 
+static_assert(!std::is_abstract_v<rtc::RefCountedObject<MockRtpTransceiver>>);
+
 }  // namespace webrtc
 
 #endif  // API_TEST_MOCK_RTP_TRANSCEIVER_H_
diff --git a/api/test/mock_rtpreceiver.h b/api/test/mock_rtpreceiver.h
index 4bcf064..5adc1aa 100644
--- a/api/test/mock_rtpreceiver.h
+++ b/api/test/mock_rtpreceiver.h
@@ -19,8 +19,12 @@
 
 namespace webrtc {
 
-class MockRtpReceiver : public rtc::RefCountedObject<RtpReceiverInterface> {
+class MockRtpReceiver : public RtpReceiverInterface {
  public:
+  static rtc::scoped_refptr<MockRtpReceiver> Create() {
+    return rtc::make_ref_counted<MockRtpReceiver>();
+  }
+
   MOCK_METHOD(rtc::scoped_refptr<MediaStreamTrackInterface>,
               track,
               (),
@@ -38,8 +42,13 @@
               (absl::optional<double>),
               (override));
   MOCK_METHOD(std::vector<RtpSource>, GetSources, (), (const, override));
+
+ protected:
+  MockRtpReceiver() = default;
 };
 
+static_assert(!std::is_abstract_v<rtc::RefCountedObject<MockRtpReceiver>>);
+
 }  // namespace webrtc
 
 #endif  // API_TEST_MOCK_RTPRECEIVER_H_
diff --git a/api/test/mock_rtpsender.h b/api/test/mock_rtpsender.h
index e2351f8..1a71d8b 100644
--- a/api/test/mock_rtpsender.h
+++ b/api/test/mock_rtpsender.h
@@ -15,6 +15,7 @@
 #include <string>
 #include <vector>
 
+#include "api/make_ref_counted.h"
 #include "api/rtp_sender_interface.h"
 #include "test/gmock.h"
 
@@ -68,7 +69,8 @@
               (override));
 };
 
-static_assert(!std::is_abstract_v<rtc::RefCountedObject<MockRtpSender>>, "");
+static_assert(!std::is_abstract_v<rtc::RefCountedObject<MockRtpSender>>);
+
 }  // namespace webrtc
 
 #endif  // API_TEST_MOCK_RTPSENDER_H_
diff --git a/api/test/mock_transformable_video_frame.h b/api/test/mock_transformable_video_frame.h
index 5cebcab..c85b05d 100644
--- a/api/test/mock_transformable_video_frame.h
+++ b/api/test/mock_transformable_video_frame.h
@@ -18,13 +18,20 @@
 
 namespace webrtc {
 
-class MockTransformableVideoFrame
-    : public webrtc::TransformableVideoFrameInterface {
+class MockTransformableVideoFrame : public TransformableVideoFrameInterface {
  public:
+  // TransformableFrameInterface
   MOCK_METHOD(rtc::ArrayView<const uint8_t>, GetData, (), (const, override));
   MOCK_METHOD(void, SetData, (rtc::ArrayView<const uint8_t> data), (override));
-  MOCK_METHOD(uint32_t, GetTimestamp, (), (const, override));
+  MOCK_METHOD(uint8_t, GetPayloadType, (), (const, override));
   MOCK_METHOD(uint32_t, GetSsrc, (), (const, override));
+  MOCK_METHOD(uint32_t, GetTimestamp, (), (const, override));
+  MOCK_METHOD(TransformableVideoFrameInterface::Direction,
+              GetDirection,
+              (),
+              (const, override));
+
+  // TransformableVideoFrameInterface
   MOCK_METHOD(bool, IsKeyFrame, (), (const, override));
   MOCK_METHOD(std::vector<uint8_t>, GetAdditionalData, (), (const, override));
   MOCK_METHOD(const webrtc::VideoFrameMetadata&,
@@ -33,6 +40,8 @@
               (const, override));
 };
 
+static_assert(!std::is_abstract_v<MockTransformableVideoFrame>);
+
 }  // namespace webrtc
 
 #endif  // API_TEST_MOCK_TRANSFORMABLE_VIDEO_FRAME_H_
diff --git a/api/test/mock_video_bitrate_allocator.h b/api/test/mock_video_bitrate_allocator.h
index 76cf49e..8f86ba0 100644
--- a/api/test/mock_video_bitrate_allocator.h
+++ b/api/test/mock_video_bitrate_allocator.h
@@ -23,6 +23,8 @@
               (override));
 };
 
+static_assert(!std::is_abstract_v<MockVideoBitrateAllocator>);
+
 }  // namespace webrtc
 
 #endif  // API_TEST_MOCK_VIDEO_BITRATE_ALLOCATOR_H_
diff --git a/api/test/mock_video_bitrate_allocator_factory.h b/api/test/mock_video_bitrate_allocator_factory.h
index 16af191..562efd7 100644
--- a/api/test/mock_video_bitrate_allocator_factory.h
+++ b/api/test/mock_video_bitrate_allocator_factory.h
@@ -18,8 +18,7 @@
 
 namespace webrtc {
 
-class MockVideoBitrateAllocatorFactory
-    : public webrtc::VideoBitrateAllocatorFactory {
+class MockVideoBitrateAllocatorFactory : public VideoBitrateAllocatorFactory {
  public:
   ~MockVideoBitrateAllocatorFactory() override { Die(); }
   MOCK_METHOD(std::unique_ptr<VideoBitrateAllocator>,
@@ -29,6 +28,8 @@
   MOCK_METHOD(void, Die, ());
 };
 
+static_assert(!std::is_abstract_v<MockVideoBitrateAllocatorFactory>);
+
 }  // namespace webrtc
 
 #endif  // API_TEST_MOCK_VIDEO_BITRATE_ALLOCATOR_FACTORY_H_
diff --git a/api/test/mock_video_decoder.h b/api/test/mock_video_decoder.h
index 34f732c..ddef1b4 100644
--- a/api/test/mock_video_decoder.h
+++ b/api/test/mock_video_decoder.h
@@ -37,6 +37,8 @@
               (override));
 };
 
+static_assert(!std::is_abstract_v<MockDecodedImageCallback>);
+
 class MockVideoDecoder : public VideoDecoder {
  public:
   MockVideoDecoder() {
@@ -65,6 +67,8 @@
   MOCK_METHOD(void, Destruct, (), ());
 };
 
+static_assert(!std::is_abstract_v<MockVideoDecoder>);
+
 }  // namespace webrtc
 
 #endif  // API_TEST_MOCK_VIDEO_DECODER_H_
diff --git a/api/test/mock_video_decoder_factory.h b/api/test/mock_video_decoder_factory.h
index 6150d9f..e61892f 100644
--- a/api/test/mock_video_decoder_factory.h
+++ b/api/test/mock_video_decoder_factory.h
@@ -35,6 +35,9 @@
               (override));
   MOCK_METHOD(void, Die, ());
 };
+
+static_assert(!std::is_abstract_v<MockVideoDecoderFactory>);
+
 }  // namespace webrtc
 
 #endif  // API_TEST_MOCK_VIDEO_DECODER_FACTORY_H_
diff --git a/api/test/mock_video_encoder.h b/api/test/mock_video_encoder.h
index 11e0f64..c6276a5 100644
--- a/api/test/mock_video_encoder.h
+++ b/api/test/mock_video_encoder.h
@@ -27,6 +27,8 @@
   MOCK_METHOD(void, OnDroppedFrame, (DropReason reason), (override));
 };
 
+static_assert(!std::is_abstract_v<MockEncodedImageCallback>);
+
 class MockVideoEncoder : public VideoEncoder {
  public:
   MOCK_METHOD(void,
@@ -68,6 +70,8 @@
   MOCK_METHOD(EncoderInfo, GetEncoderInfo, (), (const, override));
 };
 
+static_assert(!std::is_abstract_v<MockVideoEncoder>);
+
 }  // namespace webrtc
 
 #endif  // API_TEST_MOCK_VIDEO_ENCODER_H_
diff --git a/api/test/mock_video_encoder_factory.h b/api/test/mock_video_encoder_factory.h
index 02ee7aa..427c6a0 100644
--- a/api/test/mock_video_encoder_factory.h
+++ b/api/test/mock_video_encoder_factory.h
@@ -37,6 +37,8 @@
   MOCK_METHOD(void, Die, ());
 };
 
+static_assert(!std::is_abstract_v<MockVideoEncoderFactory>);
+
 }  // namespace webrtc
 
 #endif  // API_TEST_MOCK_VIDEO_ENCODER_FACTORY_H_
diff --git a/api/test/mock_video_track.h b/api/test/mock_video_track.h
index 705d135..99247f1 100644
--- a/api/test/mock_video_track.h
+++ b/api/test/mock_video_track.h
@@ -13,18 +13,17 @@
 
 #include <string>
 
+#include "api/make_ref_counted.h"
 #include "api/media_stream_interface.h"
 #include "api/scoped_refptr.h"
-#include "rtc_base/ref_counted_object.h"
 #include "test/gmock.h"
 
 namespace webrtc {
 
-class MockVideoTrack final
-    : public rtc::RefCountedObject<webrtc::VideoTrackInterface> {
+class MockVideoTrack : public webrtc::VideoTrackInterface {
  public:
   static rtc::scoped_refptr<MockVideoTrack> Create() {
-    return rtc::scoped_refptr<MockVideoTrack>(new MockVideoTrack());
+    return rtc::make_ref_counted<MockVideoTrack>();
   }
 
   // NotifierInterface
@@ -62,8 +61,13 @@
 
   MOCK_METHOD(ContentHint, content_hint, (), (const, override));
   MOCK_METHOD(void, set_content_hint, (ContentHint hint), (override));
+
+ protected:
+  MockVideoTrack() = default;
 };
 
+static_assert(!std::is_abstract_v<rtc::RefCountedObject<MockVideoTrack>>);
+
 }  // namespace webrtc
 
 #endif  // API_TEST_MOCK_VIDEO_TRACK_H_