Remove WebRtcVideoSendStream2::VideoSink inheritance. Remove sending black frame on source remova…

webrtc/media/engine/webrtcvideoengine2.h

Index: webrtc/media/engine/webrtcvideoengine2.h
diff --git a/webrtc/media/engine/webrtcvideoengine2.h b/webrtc/media/engine/webrtcvideoengine2.h
index 1fb794eece5f78cf3b1801532a0560db0ef8d414..b50c5a148eacd1245b575a58dd450d14e5699ed8 100644
--- a/webrtc/media/engine/webrtcvideoengine2.h
+++ b/webrtc/media/engine/webrtcvideoengine2.h
@@ -231,11 +231,9 @@ class WebRtcVideoChannel2 : public VideoMediaChannel, public webrtc::Transport {
   static std::string CodecSettingsVectorToString(
       const std::vector<VideoCodecSettings>& codecs);
 
-  // Wrapper for the sender part, this is where the source is connected and
-  // frames are then converted from cricket frames to webrtc frames.
+  // Wrapper for the sender part.
   class WebRtcVideoSendStream
-      : public rtc::VideoSinkInterface<webrtc::VideoFrame>,
-        public rtc::VideoSourceInterface<webrtc::VideoFrame> {
+      : public rtc::VideoSourceInterface<webrtc::VideoFrame> {
    public:
     WebRtcVideoSendStream(
         webrtc::Call* call,
@@ -256,14 +254,12 @@ class WebRtcVideoChannel2 : public VideoMediaChannel, public webrtc::Transport {
 
     // Implements rtc::VideoSourceInterface<webrtc::VideoFrame>.
     // WebRtcVideoSendStream acts as a source to the webrtc::VideoSendStream
-    // in |stream_|.
-    // TODO(perkj, nisse): Refactor WebRtcVideoSendStream to directly connect
-    // the camera input |source_|
-    void AddOrUpdateSink(VideoSinkInterface<webrtc::VideoFrame>* sink,
+    // in |stream_|. This is done to proxy VideoSinkWants from the encoder to
+    // the worker thread.
+    void AddOrUpdateSink(rtc::VideoSinkInterface<webrtc::VideoFrame>* sink,
                          const rtc::VideoSinkWants& wants) override;
-    void RemoveSink(VideoSinkInterface<webrtc::VideoFrame>* sink) override;
+    void RemoveSink(rtc::VideoSinkInterface<webrtc::VideoFrame>* sink) override;
 
-    void OnFrame(const webrtc::VideoFrame& frame) override;
     bool SetVideoSend(bool mute,
                       const VideoOptions* options,
                       rtc::VideoSourceInterface<webrtc::VideoFrame>* source);
@@ -306,21 +302,6 @@ class WebRtcVideoChannel2 : public VideoMediaChannel, public webrtc::Transport {
       bool external;
     };
 
-    // TODO(perkj): VideoFrameInfo is currently used for sending a black frame
-    // when the video source is removed. Consider moving that logic to
-    // VieEncoder or remove it.
-    struct VideoFrameInfo {
-      VideoFrameInfo()
-          : width(0),
-            height(0),
-            rotation(webrtc::kVideoRotation_0),
-            is_texture(false) {}
-      int width;
-      int height;
-      webrtc::VideoRotation rotation;
-      bool is_texture;
-    };
-
     rtc::scoped_refptr<webrtc::VideoEncoderConfig::EncoderSpecificSettings>
     ConfigureVideoEncoderSettings(const VideoCodec& codec);
     AllocatedEncoder CreateVideoEncoder(const VideoCodec& codec);
@@ -348,10 +329,9 @@ class WebRtcVideoChannel2 : public VideoMediaChannel, public webrtc::Transport {
     WebRtcVideoEncoderFactory* const external_encoder_factory_
         ACCESS_ON(&thread_checker_);
 
-    rtc::CriticalSection lock_;
     webrtc::VideoSendStream* stream_ ACCESS_ON(&thread_checker_);
     rtc::VideoSinkInterface<webrtc::VideoFrame>* encoder_sink_
-        GUARDED_BY(lock_);
+        ACCESS_ON(&thread_checker_);
     // Contains settings that are the same for all streams in the MediaChannel,
     // such as codecs, header extensions, and the global bitrate limit for the
     // entire channel.
@@ -363,13 +343,8 @@ class WebRtcVideoChannel2 : public VideoMediaChannel, public webrtc::Transport {
     // one stream per MediaChannel.
     webrtc::RtpParameters rtp_parameters_ ACCESS_ON(&thread_checker_);
     AllocatedEncoder allocated_encoder_ ACCESS_ON(&thread_checker_);
-    VideoFrameInfo last_frame_info_ GUARDED_BY(lock_);
 
     bool sending_ ACCESS_ON(&thread_checker_);
-
-    // The timestamp of the last frame received
-    // Used to generate timestamp for the black frame when source is removed
-    int64_t last_frame_timestamp_us_ GUARDED_BY(lock_);
   };
 
   // Wrapper for the receiver part, contains configs etc. that are needed to