Allow to use {FFmpeg/Vpx}VideoDecoder from a UtilityProcess

media/mojo/common/mojo_video_frame_provider.cc

+// Copyright 2017 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.
+
+#include "media/mojo/common/mojo_video_frame_provider.h"
+
+#include "media/mojo/common/mojo_shared_buffer_video_frame.h"
+
+namespace media {
+
+MojoVideoFrameProvider::MojoVideoFrameProvider() {}
+
+MojoVideoFrameProvider::~MojoVideoFrameProvider() {}
+
+scoped_refptr<VideoFrame> MojoVideoFrameProvider::CreateZeroInitializedFrame(
+    VideoPixelFormat format,
+    const gfx::Size& coded_size,
+    const gfx::Rect& visible_rect,
+    const gfx::Size& natural_size,
+    base::TimeDelta timestamp) {
+  // TODO(j.isorce): handle above sizes and implement
+  // MojoSharedBufferVideoFrame::CreateZeroInitializedFrame.
+  return MojoSharedBufferVideoFrame::CreateYUV(format, natural_size, timestamp);
+}
+
+scoped_refptr<VideoFrame> MojoVideoFrameProvider::WrapVideoFrame(
+    const scoped_refptr<VideoFrame>& frame) {
+  DCHECK(frame->storage_type() == VideoFrame::STORAGE_MOJO_SHARED_BUFFER);
+
+  return MojoSharedBufferVideoFrame::WrapMojoSharedBufferVideoFrame(
+      static_cast<media::MojoSharedBufferVideoFrame*>(frame.get()));
+}
+
+}  // namespace media