[Chromecast] Upgrade to new CMA backend API

chromecast/media/cma/pipeline/video_pipeline_device_client_impl.cc

-// Copyright 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.
-
-#include "chromecast/media/cma/pipeline/video_pipeline_device_client_impl.h"
-
-#include "base/bind.h"
-#include "base/location.h"
-#include "base/single_thread_task_runner.h"
-#include "base/thread_task_runner_handle.h"
-#include "chromecast/public/graphics_types.h"
-
-namespace chromecast {
-namespace media {
-
-VideoPipelineDeviceClientImpl::VideoPipelineDeviceClientImpl(
-    const SizeChangeCB& size_change_cb)
-    : size_change_cb_(size_change_cb),
-      task_runner_(base::ThreadTaskRunnerHandle::Get()) {}
-
-VideoPipelineDeviceClientImpl::~VideoPipelineDeviceClientImpl() {}
-
-void VideoPipelineDeviceClientImpl::OnNaturalSizeChanged(const Size& size) {
-  if (task_runner_->BelongsToCurrentThread()) {
-    if (!size_change_cb_.is_null())
-      size_change_cb_.Run(size);
-  } else {
-    task_runner_->PostTask(FROM_HERE, base::Bind(size_change_cb_, size));
-  }
-}
-
-}  // namespace media
-}  // namespace chromecast