Enable Cyclic Refresh for VP9.

remoting/codec/video_encoder_vpx.h

Index: remoting/codec/video_encoder_vpx.h
diff --git a/remoting/codec/video_encoder_vpx.h b/remoting/codec/video_encoder_vpx.h
index a7433a16d9b7068ffa8da54c03b4db47654c94b6..3cc396629ab1778ee35ce521622cd62217698749 100644
--- a/remoting/codec/video_encoder_vpx.h
+++ b/remoting/codec/video_encoder_vpx.h
@@ -49,6 +49,9 @@ class VideoEncoderVpx : public VideoEncoder {
   // given to the encoder to speed up encoding.
   void PrepareActiveMap(const webrtc::DesktopRegion& updated_region);
 
+  // Updates the active map to revealing areas updated by cyclic refresh.

[Wez, 2015/04/18 00:17:55]

This doesn't seem to update the active map at all; it fetches the active map
that the encoder actually used for the frame, combining the caller-supplied
active map with the areas updated by cyclic refresh, right?

Suggest changing PrepareActiveMap() and UpdateActiveMap() to
SetActiveMap[FromRegion](...) and GetActiveMap[ToRegion](...). The *Region forms
seem clearer to read, but more verbose, so up to you.

[aconverse, 2015/04/20 18:32:39]

Done.

+  void UpdateActiveMap(webrtc::DesktopRegion* updated_region);
+
   // True if the encoder is for VP9, false for VP8.
   const bool use_vp9_;