Introduce TimeSource notifications to the VideoRenderer.

media/base/video_renderer.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef MEDIA_BASE_VIDEO_RENDERER_H_
 #define MEDIA_BASE_VIDEO_RENDERER_H_
 
 #include "base/callback.h"
 #include "base/memory/ref_counted.h"
 #include "base/time/time.h"
@@ skipping 64 matching lines @@
   // Clients should expect |buffering_state_cb| to be called with
   // BUFFERING_HAVE_NOTHING while flushing is in progress.
   virtual void Flush(const base::Closure& callback) = 0;
 
   // Starts playback at |timestamp| by reading from |stream| and decoding and
   // rendering video.
   //
   // Only valid to call after a successful Initialize() or Flush().
   virtual void StartPlayingFrom(base::TimeDelta timestamp) = 0;
 
+  // Called when time starts ticking and the playback rate is greater than 0.
+  virtual void OnTimeProgressing() = 0;
+
+  // Called when time stops ticking or the playback rate is zero.
+  virtual void OnTimeStopped() = 0;
+
  private:
   DISALLOW_COPY_AND_ASSIGN(VideoRenderer);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_VIDEO_RENDERER_H_