Switch to using media::TimeSource inside media::RendererImpl.

media/base/time_source.h

Index: media/base/time_source.h
diff --git a/media/base/time_source.h b/media/base/time_source.h
index 2c5a72028e9fe3b27dc7f7c87f74fb20feafb65c..8ad364b20a2dda21d97d087a93f878bc0bef16e1 100644
--- a/media/base/time_source.h
+++ b/media/base/time_source.h
@@ -34,7 +34,23 @@ class MEDIA_EXPORT TimeSource {
   virtual void SetMediaTime(base::TimeDelta time) = 0;
 
   // Returns the current media time.
+  //
+  // Values returned are intended for informational purposes, such as displaying
+  // UI with the current minute and second count. While it is guaranteed values
+  // will never go backwards, the frequency at which they update may be low.
   virtual base::TimeDelta CurrentMediaTime() = 0;
+
+  // Returns the current media time for use with synchronizing video.
+  //
+  // Differences from CurrentMediaTime():
+  //   - Values returned update at a much higher frequency (e.g., suitable for
+  //     playback of 60 FPS content).
+  //   - As a result, values may go slightly backwards depending on the
+  //     implementation (e.g., uses interpolation).
+  //
+  // TODO(scherkus): Replace with a method that returns wall clock time for a
+  // given media time for use with VideoFrameScheduler http://crbug.com/110814
+  virtual base::TimeDelta CurrentMediaTimeForSyncingVideo() = 0;
 };
 
 }  // namespace media