Allow Preroll() call on VideoRendererImpl without a Flush().

media/filters/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_FILTERS_VIDEO_RENDERER_IMPL_H_
 #define MEDIA_FILTERS_VIDEO_RENDERER_IMPL_H_
 
 #include <deque>
 
 #include "base/memory/ref_counted.h"
@@ skipping 111 matching lines @@
   // A read is scheduled to replace the frame.
   void PaintNextReadyFrame_Locked();
 
   // Drops the next frame from |ready_frames_| and runs |statistics_cb_|.
   //
   // A read is scheduled to replace the frame.
   void DropNextReadyFrame_Locked();
 
   void TransitionToPrerolled_Locked();
 
+  // Returns true of all conditions have been met to transition from
+  // kPrerolling to kPrerolled.
+  bool ShouldTransitionToPrerolled_Locked();
+
   // Runs |statistics_cb_| with |frames_decoded_| and |frames_dropped_|, resets
   // them to 0, and then waits on |frame_available_| for up to the
   // |wait_duration|.
   void UpdateStatsAndWait_Locked(base::TimeDelta wait_duration);
 
   scoped_refptr<base::MessageLoopProxy> message_loop_;
   base::WeakPtrFactory<VideoRendererImpl> weak_factory_;
   base::WeakPtr<VideoRendererImpl> weak_this_;
 
   // Used for accessing data members.
@@ skipping 103 matching lines @@
   // last call to |statistics_cb_|. These must be accessed under lock.
   int frames_decoded_;
   int frames_dropped_;
 
   DISALLOW_COPY_AND_ASSIGN(VideoRendererImpl);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_FILTERS_VIDEO_RENDERER_IMPL_H_