Add gpu::MailboxHolder to hold state for a gpu::Mailbox

media/filters/gpu_video_decoder.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_FILTERS_GPU_VIDEO_DECODER_H_
 #define MEDIA_FILTERS_GPU_VIDEO_DECODER_H_
 
 #include <list>
 #include <map>
 #include <set>
@@ skipping 87 matching lines @@
 
   // Enqueue a frame for later delivery (or drop it on the floor if a
   // vda->Reset() is in progress) and trigger out-of-line delivery of the oldest
   // ready frame to the client if there is a pending read.  A NULL |frame|
   // merely triggers delivery, and requires the ready_video_frames_ queue not be
   // empty.
   void EnqueueFrameAndTriggerFrameDelivery(
       const scoped_refptr<VideoFrame>& frame);
 
   // Indicate the picture buffer can be reused by the decoder.
-  void ReusePictureBuffer(int64 picture_buffer_id, uint32 sync_point);
+  void ReusePictureBuffer(int64 picture_buffer_id,
+                          scoped_ptr<gpu::MailboxHolder> mailbox_holder);
 
   void RecordBufferData(
       const BitstreamBuffer& bitstream_buffer, const DecoderBuffer& buffer);
   void GetBufferData(int32 id, base::TimeDelta* timetamp,
                      gfx::Rect* visible_rect, gfx::Size* natural_size);
 
   void DestroyVDA();
 
   // Request a shared-memory segment of at least |min_size| bytes.  Will
   // allocate as necessary.  Caller does not own returned pointer.
@@ skipping 67 matching lines @@
   // Set during ProvidePictureBuffers(), used for checking and implementing
   // HasAvailableOutputFrames().
   int available_pictures_;
 
   DISALLOW_COPY_AND_ASSIGN(GpuVideoDecoder);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_FILTERS_GPU_VIDEO_DECODER_H_