[Remoting Host] Supporting WebRTC VP9 streaming

remoting/protocol/webrtc_dummy_video_encoder.h

Index: remoting/protocol/webrtc_dummy_video_encoder.h
diff --git a/remoting/protocol/webrtc_dummy_video_encoder.h b/remoting/protocol/webrtc_dummy_video_encoder.h
index c55588a1242ffc004db535bd3cfafdfc06b15d40..15a40c22976ae9ac88ebd083af7c8a375b358941 100644
--- a/remoting/protocol/webrtc_dummy_video_encoder.h
+++ b/remoting/protocol/webrtc_dummy_video_encoder.h
@@ -35,7 +35,8 @@ class WebrtcDummyVideoEncoder : public webrtc::VideoEncoder {
 
   WebrtcDummyVideoEncoder(
       scoped_refptr<base::SingleThreadTaskRunner> main_task_runner,
-      base::WeakPtr<VideoChannelStateObserver> video_channel_state_observer);
+      base::WeakPtr<VideoChannelStateObserver> video_channel_state_observer,
+      webrtc::VideoCodecType type);
   ~WebrtcDummyVideoEncoder() override;
 
   // webrtc::VideoEncoder overrides.
@@ -62,6 +63,7 @@ class WebrtcDummyVideoEncoder : public webrtc::VideoEncoder {
   base::Lock lock_;
   State state_;
   webrtc::EncodedImageCallback* encoded_callback_ = nullptr;
+  webrtc::VideoCodecType codec_type_;
 
   base::WeakPtr<VideoChannelStateObserver> video_channel_state_observer_;
 };
@@ -87,6 +89,11 @@ class WebrtcDummyVideoEncoderFactory
       const WebrtcVideoEncoder::EncodedFrame& packet,
       base::TimeTicks capture_time);
 
+  // Callback will be called once the dummy encoder has been created on
+  // |main_task_runner_|.
+  void SetEncoderCreatedCallback(

[Yuwei, 2017/03/29 01:08:33]

Alternatively we can make the factory own the VPX encoder and make the video
stream directly post the frame into something like Factory::EncodeFrame().

+      const base::Callback<void(webrtc::VideoCodecType)>& callback);
+
   void SetVideoChannelStateObserver(
       base::WeakPtr<VideoChannelStateObserver> video_channel_state_observer);
   base::WeakPtr<VideoChannelStateObserver>
@@ -103,6 +110,7 @@ class WebrtcDummyVideoEncoderFactory
   base::Lock lock_;
   base::WeakPtr<VideoChannelStateObserver> video_channel_state_observer_;
   std::vector<std::unique_ptr<WebrtcDummyVideoEncoder>> encoders_;
+  base::Callback<void(webrtc::VideoCodecType)> encoder_created_callback_;
 };
 
 }  // namespace protocol