Move underflow threshold limits out of the video renderer.

media/renderers/video_renderer_impl.h

Index: media/renderers/video_renderer_impl.h
diff --git a/media/renderers/video_renderer_impl.h b/media/renderers/video_renderer_impl.h
index 6f6c027406329927ebcaee029710c59862409668..178cee2a8262d050240f87bf019b86853de66d32 100644
--- a/media/renderers/video_renderer_impl.h
+++ b/media/renderers/video_renderer_impl.h
@@ -197,10 +197,6 @@ class MEDIA_EXPORT VideoRendererImpl
   // flushing.
   base::TimeTicks last_media_time_;
 
-  // The wallclock time of the last successfully painted frame. Set to null
-  // during flushing.
-  base::TimeTicks last_painted_time_;
-
   // Keeps track of the number of frames decoded and dropped since the
   // last call to |statistics_cb_|. These must be accessed under lock.
   int frames_decoded_;