Add a GpuMemoryBuffer pool that creates hardware backed VideoFrames.

media/video/gpu_memory_buffer_video_frame_pool.h

+// Copyright (c) 2015 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_VIDEO_GPU_MEMORY_BUFFER_VIDEO_FRAME_POOL_H_
+#define MEDIA_VIDEO_GPU_MEMORY_BUFFER_VIDEO_FRAME_POOL_H_
+
+#include "base/macros.h"
+#include "base/memory/ref_counted.h"
+#include "media/base/video_frame.h"
+
+namespace base {
+class SingleThreadTaskRunner;
+}
+
+namespace media {
+class GpuVideoAcceleratorFactories;
+
+// Interface to a pool of GpuMemoryBuffers that can be used to back VideoFrames.
+// Calling the method MaybeCreateHardwareFrame with a software frame will
+// create and return a VideoFrame containing only mailboxes to the native
+// resources needed to draw. If it's not possible to create an hardware
+// VideoFrame the object passed as parameter will be returned.
+class MEDIA_EXPORT GpuMemoryBufferVideoFramePool {
+ public:
+  GpuMemoryBufferVideoFramePool(
+      const scoped_refptr<base::SingleThreadTaskRunner>& task_runner,
+      const scoped_refptr<GpuVideoAcceleratorFactories>& gpu_factories);
+  ~GpuMemoryBufferVideoFramePool();
+
+  scoped_refptr<VideoFrame> MaybeCreateHardwareFrame(

[DaleCurtis, 2015/05/14 00:58:58]

Method needs comment.

[Daniele Castagna, 2015/05/14 17:30:27]

Done.
Also rephrased the class comment.

+      const scoped_refptr<VideoFrame>& video_frame);
+
+ private:
+  class PoolImpl;
+  scoped_refptr<PoolImpl> pool_impl_;
+
+  DISALLOW_COPY_AND_ASSIGN(GpuMemoryBufferVideoFramePool);
+};
+
+}  // namespace media
+
+#endif  // MEDIA_VIDEO_GPU_MEMORY_BUFFER_VIDEO_FRAME_POOL_H_