Move underflow threshold limits out of the video renderer.

media/renderers/video_renderer_impl.h

 // Copyright 2013 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_RENDERERS_VIDEO_RENDERER_IMPL_H_
 #define MEDIA_RENDERERS_VIDEO_RENDERER_IMPL_H_
 
 #include <deque>
 
 #include "base/memory/ref_counted.h"
@@ skipping 179 matching lines @@
   base::TimeDelta start_timestamp_;
 
   // Embedder callback for notifying a new frame is available for painting.
   PaintCB paint_cb_;
 
   // The wallclock times of the last frame removed from the |ready_frames_|
   // queue, either for calling |paint_cb_| or for dropping. Set to null during
   // 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_;
+  // Equivalent to |last_media_time_| + the estimated duration of the frame.
+  base::TimeTicks latest_possible_paint_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_;
   int frames_dropped_;
 
   bool is_shutting_down_;
 
   scoped_ptr<base::TickClock> tick_clock_;
 
   // NOTE: Weak pointers must be invalidated before all other member variables.
   base::WeakPtrFactory<VideoRendererImpl> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(VideoRendererImpl);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_RENDERERS_VIDEO_RENDERER_IMPL_H_