Reland Replace interface VideoCapturerInput with VideoSinkInterface.

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 7e32116608c7e87f572c201e3485f74cf558d8ab..b8d17e8105569e44cb2320ee0cd5369b17d4adc3 100644
--- a/webrtc/media/engine/webrtcvideoengine2.h
+++ b/webrtc/media/engine/webrtcvideoengine2.h
@@ -243,6 +243,7 @@ class WebRtcVideoChannel2 : public VideoMediaChannel, public webrtc::Transport {
   // frames are then converted from cricket frames to webrtc frames.
   class WebRtcVideoSendStream
       : public rtc::VideoSinkInterface<cricket::VideoFrame>,
+        public rtc::VideoSourceInterface<webrtc::VideoFrame>,
         public webrtc::LoadObserver {
    public:
     WebRtcVideoSendStream(
@@ -262,6 +263,16 @@ class WebRtcVideoChannel2 : public VideoMediaChannel, public webrtc::Transport {
     bool SetRtpParameters(const webrtc::RtpParameters& parameters);
     webrtc::RtpParameters GetRtpParameters() const;
 
+    // Implements rtc::VideoSourceInterface<webrtc::VideoFrame>.
+    // WebRtcVideoSendStream acts as a source to the webrtc::VideoSendStream
+    // in |stream_|. The reason is that WebRtcVideoSendStream receives
+    // cricket::VideoFrames and forwards webrtc::VideoFrames to |source_|.
+    // TODO(perkj, nisse): Refactor WebRtcVideoSendStream to directly connect
+    // the camera input |source_|
+    void AddOrUpdateSink(VideoSinkInterface<webrtc::VideoFrame>* sink,
+                         const rtc::VideoSinkWants& wants) override;
+    void RemoveSink(VideoSinkInterface<webrtc::VideoFrame>* sink) override;
+
     void OnFrame(const cricket::VideoFrame& frame) override;
     bool SetVideoSend(bool mute,
                       const VideoOptions* options,
@@ -389,6 +400,8 @@ class WebRtcVideoChannel2 : public VideoMediaChannel, public webrtc::Transport {
 
     rtc::CriticalSection lock_;
     webrtc::VideoSendStream* stream_ GUARDED_BY(lock_);
+    rtc::VideoSinkInterface<webrtc::VideoFrame>* encoder_sink_
+        GUARDED_BY(lock_);
     // 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.