Load CMA backend from shared library

chromecast/media/cma/backend/media_pipeline_backend_default.h

Index: chromecast/media/cma/backend/media_pipeline_backend_default.h
diff --git a/chromecast/media/cma/backend/media_pipeline_backend_default.h b/chromecast/media/cma/backend/media_pipeline_backend_default.h
new file mode 100644
index 0000000000000000000000000000000000000000..7a9a602d68577e55b60739b1e708e336cd9818c2
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+++ b/chromecast/media/cma/backend/media_pipeline_backend_default.h
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+// 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.
+
+#ifndef CHROMECAST_MEDIA_CMA_BACKEND_MEDIA_PIPELINE_DEVICE_FACTORY_DEFAULT_H_
+#define CHROMECAST_MEDIA_CMA_BACKEND_MEDIA_PIPELINE_DEVICE_FACTORY_DEFAULT_H_
+
+#include "base/memory/scoped_ptr.h"
+#include "chromecast/public/media/media_pipeline_backend.h"
+#include "chromecast/public/media/media_pipeline_device_params.h"
+
+namespace chromecast {
+namespace media {
+
+// Factory that instantiates default (stub) media pipeline device elements.
+class MediaPipelineBackendDefault : public MediaPipelineBackend {
+ public:
+  MediaPipelineBackendDefault(const MediaPipelineDeviceParams& params);
+  ~MediaPipelineBackendDefault() override;
+
+  // MediaPipelineBackend implementation
+  MediaClockDevice* GetClock() override;
+  AudioPipelineDevice* GetAudio() override;
+  VideoPipelineDevice* GetVideo() override;
+
+ private:
+  MediaPipelineDeviceParams params_;
+  scoped_ptr<MediaClockDevice> clock_;
+  scoped_ptr<AudioPipelineDevice> audio_;
+  scoped_ptr<VideoPipelineDevice> video_;
+
+  DISALLOW_COPY_AND_ASSIGN(MediaPipelineBackendDefault);
+};
+
+}  // namespace media
+}  // namespace chromecast
+
+#endif  // CHROMECAST_MEDIA_CMA_BACKEND_MEDIA_PIPELINE_DEVICE_FACTORY_DEFAULT_H_