Load CMA backend from shared library

chromecast/media/cma/backend/media_pipeline_device_factory_default.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/backend/media_pipeline_device_factory_default.h"
-
-#include "chromecast/media/cma/backend/audio_pipeline_device_default.h"
-#include "chromecast/media/cma/backend/media_clock_device_default.h"
-#include "chromecast/media/cma/backend/video_pipeline_device_default.h"
-
-namespace chromecast {
-namespace media {
-
-MediaPipelineDeviceFactoryDefault::MediaPipelineDeviceFactoryDefault()
-    : clock_(nullptr) {
-}
-
-scoped_ptr<MediaClockDevice>
-MediaPipelineDeviceFactoryDefault::CreateMediaClockDevice() {
-  DCHECK(!clock_);
-  clock_ = new MediaClockDeviceDefault();
-  return make_scoped_ptr(clock_);
-}
-
-scoped_ptr<AudioPipelineDevice>
-MediaPipelineDeviceFactoryDefault::CreateAudioPipelineDevice() {
-  DCHECK(clock_);
-  return make_scoped_ptr(new AudioPipelineDeviceDefault(clock_));
-}
-
-scoped_ptr<VideoPipelineDevice>
-MediaPipelineDeviceFactoryDefault::CreateVideoPipelineDevice() {
-  DCHECK(clock_);
-  return make_scoped_ptr(new VideoPipelineDeviceDefault(clock_));
-}
-
-}  // namespace media
-}  // namespace chromecast