Remove reference counting from media::Pipeline.

media/base/pipeline.h

Index: media/base/pipeline.h
diff --git a/media/base/pipeline.h b/media/base/pipeline.h
index aa922692a9b5e0d613562c1859ad62bd5862f347..a91176e5a8f60dd6a4a63688568a97bc89b020d3 100644
--- a/media/base/pipeline.h
+++ b/media/base/pipeline.h
@@ -63,9 +63,7 @@ class VideoRenderer;
 // If any error ever happens, this object will transition to the "Error" state
 // from any state. If Stop() is ever called, this object will transition to
 // "Stopped" state.
-class MEDIA_EXPORT Pipeline
-    : public base::RefCountedThreadSafe<Pipeline>,
-      public DemuxerHost {
+class MEDIA_EXPORT Pipeline : public DemuxerHost {
  public:
   // Buffering states the pipeline transitions between during playback.
   // kHaveMetadata:
@@ -85,6 +83,7 @@ class MEDIA_EXPORT Pipeline
   // Constructs a media pipeline that will execute on |message_loop|.
   Pipeline(const scoped_refptr<base::MessageLoopProxy>& message_loop,
            MediaLog* media_log);
+  virtual ~Pipeline();
 
   // Build a pipeline to using the given filter collection to construct a filter
   // chain, executing |seek_cb| when the initial seek/preroll has completed.
@@ -198,10 +197,6 @@ class MEDIA_EXPORT Pipeline
   FRIEND_TEST_ALL_PREFIXES(PipelineTest, AudioStreamShorterThanVideo);
   friend class MediaLog;
 
-  // Only allow ourselves to be deleted by reference counting.
-  friend class base::RefCountedThreadSafe<Pipeline>;
-  virtual ~Pipeline();
-
   // Pipeline states, as described above.
   enum State {
     kCreated,