Add default dummy implementation of cricket::VideoRenderer::SetSize, to easy later removal.

talk/media/base/videorenderer.h

 /*
  * libjingle
  * Copyright 2004 Google Inc.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
  *
  *  1. Redistributions of source code must retain the above copyright notice,
  *     this list of conditions and the following disclaimer.
  *  2. Redistributions in binary form must reproduce the above copyright notice,
@@ skipping 24 matching lines @@
 #include "webrtc/base/sigslot.h"
 
 namespace cricket {
 
 class VideoFrame;
 
 // Abstract interface for rendering VideoFrames.
 class VideoRenderer {
  public:
   virtual ~VideoRenderer() {}
-  // Called when the video has changed size. This is also used as an
-  // initialization method to set the UI size before any video frame
-  // rendered. webrtc::ExternalRenderer's FrameSizeChange will invoke this when
-  // it's called or later when a VideoRenderer is attached.
-  virtual bool SetSize(int width, int height, int reserved) = 0;
+  // Called when the video has changed size.
+  // TODO(nisse): This method is not really used, and should be
+  // deleted. Provide a default do-nothing implementation, to easy the
+  // transition as the method is deleted in subclasses, in particular,
+  // chrome's MockVideoRenderer class.
+  virtual bool SetSize(int width, int height, int reserved) { return true; };
   // Called when a new frame is available for display.
   virtual bool RenderFrame(const VideoFrame *frame) = 0;
 
 #if !defined(NDEBUG)
   // Allow renderer dumping out rendered frames.
   virtual bool SetDumpPath(const std::string &path) { return true; }
 #endif
 };
 
 }  // namespace cricket
 
 #endif  // TALK_MEDIA_BASE_VIDEORENDERER_H_