Adding callback support to media filter Initialize() and Seek().

media/filters/video_renderer_base.h

Index: media/filters/video_renderer_base.h
diff --git a/media/filters/video_renderer_base.h b/media/filters/video_renderer_base.h
index e71befa96a0cb5b89be53c97dc48e6f59b252440..b1b46abcd56b953617b5dc7a09de2e1dead398b3 100644
--- a/media/filters/video_renderer_base.h
+++ b/media/filters/video_renderer_base.h
@@ -39,10 +39,10 @@ class VideoRendererBase : public VideoRenderer,
   // MediaFilter implementation.
   virtual void Stop();
   virtual void SetPlaybackRate(float playback_rate);
-  virtual void Seek(base::TimeDelta time);
+  virtual void Seek(base::TimeDelta time, FilterCallback* callback);
 
   // VideoRenderer implementation.
-  virtual bool Initialize(VideoDecoder* decoder);
+  virtual void Initialize(VideoDecoder* decoder, FilterCallback* callback);
 
   // PlatformThread::Delegate implementation.
   virtual void ThreadMain();
@@ -106,6 +106,7 @@ class VideoRendererBase : public VideoRenderer,
     INITIALIZING,
     INITIALIZED,
     STOPPED,
+    ERRORED,
   };
   State state_;
 
@@ -117,6 +118,9 @@ class VideoRendererBase : public VideoRenderer,
 
   float playback_rate_;
 
+  // Filter callbacks.
+  scoped_ptr<FilterCallback> initialize_callback_;
+
   DISALLOW_COPY_AND_ASSIGN(VideoRendererBase);
 };