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

cc/resources/video_resource_updater.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 CC_RESOURCES_VIDEO_RESOURCE_UPDATER_H_
 #define CC_RESOURCES_VIDEO_RESOURCE_UPDATER_H_
 
 #include <vector>
 
 #include "base/basictypes.h"
@@ skipping 86 matching lines @@
       const scoped_refptr<media::VideoFrame>& video_frame);
 
   struct RecycleResourceData {
     unsigned resource_id;
     gfx::Size resource_size;
     ResourceFormat resource_format;
     gpu::Mailbox mailbox;
   };
   static void RecycleResource(base::WeakPtr<VideoResourceUpdater> updater,
                               RecycleResourceData data,
-                              unsigned sync_point,
+                              uint32 sync_point,
                               bool lost_resource);
 
   ContextProvider* context_provider_;
   ResourceProvider* resource_provider_;
   scoped_ptr<media::SkCanvasVideoRenderer> video_renderer_;
 
   std::vector<unsigned> all_resources_;
   std::vector<PlaneResource> recycled_resources_;
 
   DISALLOW_COPY_AND_ASSIGN(VideoResourceUpdater);
 };
 
 }  // namespace cc
 
 #endif  // CC_RESOURCES_VIDEO_RESOURCE_UPDATER_H_