Split out dscp option from VideoOptions to new struct MediaChannelOptions.

talk/media/webrtc/webrtcvideoengine2.h

Index: talk/media/webrtc/webrtcvideoengine2.h
diff --git a/talk/media/webrtc/webrtcvideoengine2.h b/talk/media/webrtc/webrtcvideoengine2.h
index eff1a612c82a74708e0e17a2ee86655bbf212e50..59f390cdf4b06708d58aff074db9f7e68e71061d 100644
--- a/talk/media/webrtc/webrtcvideoengine2.h
+++ b/talk/media/webrtc/webrtcvideoengine2.h
@@ -114,7 +114,8 @@ class WebRtcVideoEngine2 {
   void Init();
 
   WebRtcVideoChannel2* CreateChannel(webrtc::Call* call,
-                                     const VideoOptions& options);
+                                     const MediaChannelOptions& options,
+                                     const VideoOptions& video_options);
 
   const std::vector<VideoCodec>& codecs() const;
   RtpCapabilities GetCapabilities() const;
@@ -151,13 +152,15 @@ class WebRtcVideoChannel2 : public rtc::MessageHandler,
                             public webrtc::LoadObserver {
  public:
   WebRtcVideoChannel2(webrtc::Call* call,
-                      const VideoOptions& options,
+                      const MediaChannelOptions& options,
+                      const VideoOptions& video_options,
                       const std::vector<VideoCodec>& recv_codecs,
                       WebRtcVideoEncoderFactory* external_encoder_factory,
                       WebRtcVideoDecoderFactory* external_decoder_factory);
   ~WebRtcVideoChannel2() override;
 
   // VideoMediaChannel implementation
+  rtc::DiffServCodePoint DscpValue() const override;
   bool SetSendParameters(const VideoSendParameters& params) override;
   bool SetRecvParameters(const VideoRecvParameters& params) override;
   bool GetSendCodec(VideoCodec* send_codec) override;