Load CMA backend from shared library

chromecast/public/media/audio_pipeline_device.h

Index: chromecast/public/media/audio_pipeline_device.h
diff --git a/chromecast/media/cma/backend/audio_pipeline_device.h b/chromecast/public/media/audio_pipeline_device.h
similarity index 73%
rename from chromecast/media/cma/backend/audio_pipeline_device.h
rename to chromecast/public/media/audio_pipeline_device.h
index 84c1af1fe1d9c1fb42bfe3db3a514b25f5eba4a5..c2d6b9b0ad918a2f874c5fd3126df5209192e9bc 100644
--- a/chromecast/media/cma/backend/audio_pipeline_device.h
+++ b/chromecast/public/media/audio_pipeline_device.h
@@ -2,11 +2,10 @@
 // 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_AUDIO_PIPELINE_DEVICE_H_
-#define CHROMECAST_MEDIA_CMA_BACKEND_AUDIO_PIPELINE_DEVICE_H_
+#ifndef CHROMECAST_PUBLIC_MEDIA_AUDIO_PIPELINE_DEVICE_H_
+#define CHROMECAST_PUBLIC_MEDIA_AUDIO_PIPELINE_DEVICE_H_
 
-#include "base/macros.h"
-#include "chromecast/media/cma/backend/media_component_device.h"
+#include "media_component_device.h"
 
 namespace chromecast {
 namespace media {
@@ -15,8 +14,7 @@ struct AudioConfig;
 
 class AudioPipelineDevice : public MediaComponentDevice {
  public:
-  AudioPipelineDevice();
-  ~AudioPipelineDevice() override;
+  ~AudioPipelineDevice() override {}
 
   // Provide the audio configuration.
   // Must be called before switching from |kStateUninitialized| to |kStateIdle|.
@@ -27,9 +25,6 @@ class AudioPipelineDevice : public MediaComponentDevice {
   // Sets the volume multiplier.
   // The multiplier must be in the range [0.0, 1.0].
   virtual void SetStreamVolumeMultiplier(float multiplier) = 0;
-
- private:
-  DISALLOW_COPY_AND_ASSIGN(AudioPipelineDevice);
 };
 
 }  // namespace media