[Chromecast] Upgrade to new CMA backend API

chromecast/browser/media/cma_media_pipeline_client.h

Index: chromecast/browser/media/cma_media_pipeline_client.h
diff --git a/chromecast/browser/media/cma_media_pipeline_client.h b/chromecast/browser/media/cma_media_pipeline_client.h
index f7ecd4b80429d2c3e3eb6aefafbb6da7fc29426e..b711b6fbe40d5d01636ab20af4dc6a09fb399b31 100644
--- a/chromecast/browser/media/cma_media_pipeline_client.h
+++ b/chromecast/browser/media/cma_media_pipeline_client.h
@@ -14,6 +14,8 @@
 namespace chromecast {
 namespace media {
 
+struct MediaPipelineDeviceParams;
+
 // Class to provide media backend and watch media pipeline status
 class CmaMediaPipelineClient : public base::RefCounted<CmaMediaPipelineClient>,
                                public CastResource {
@@ -21,7 +23,7 @@ class CmaMediaPipelineClient : public base::RefCounted<CmaMediaPipelineClient>,
   CmaMediaPipelineClient();
 
   virtual scoped_ptr<MediaPipelineBackend> CreateMediaPipelineBackend(
-      const media::MediaPipelineDeviceParams& params);
+      const MediaPipelineDeviceParams& params);
 
   virtual void OnMediaPipelineBackendCreated();
   virtual void OnMediaPipelineBackendDestroyed();