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

talk/media/base/videorenderer.h

Index: talk/media/base/videorenderer.h
diff --git a/talk/media/base/videorenderer.h b/talk/media/base/videorenderer.h
index 0a0ee5181712596e2afe1463efef9b6e356b0515..a18c4e3c2966e9e803f6ef781765c65b01e073c5 100644
--- a/talk/media/base/videorenderer.h
+++ b/talk/media/base/videorenderer.h
@@ -42,11 +42,12 @@ class VideoFrame;
 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;