Move VideoDecoder out of media pipeline.

media/base/filters.h

Index: media/base/filters.h
diff --git a/media/base/filters.h b/media/base/filters.h
index 4823cf8935509eeb901e24c8aebe826dfa3b7c1d..606cb42d9b327cdc940dfff5d292e56e82a32e62 100644
--- a/media/base/filters.h
+++ b/media/base/filters.h
@@ -159,8 +159,17 @@ class MEDIA_EXPORT VideoDecoder : public Filter {
  protected:
   VideoDecoder();
   virtual ~VideoDecoder();
-};
 
+ private:
+  // These functions will be removed later. Declare here to make sure they are
+  // not called from VideoDecoder interface anymore.
+  // TODO(xhwang): Remove them when VideoDecoder is not a Filter any more.
+  // See bug: crbug.com/108340
+  virtual void Play(const base::Closure& callback) OVERRIDE;
+  virtual void Pause(const base::Closure& callback) OVERRIDE;
+  virtual void Seek(base::TimeDelta time,
+                    const PipelineStatusCB& callback) OVERRIDE;
+};
 
 class MEDIA_EXPORT VideoRenderer : public Filter {
  public:
@@ -170,7 +179,7 @@ class MEDIA_EXPORT VideoRenderer : public Filter {
 
   // Initialize a VideoRenderer with the given VideoDecoder, executing the
   // callback upon completion.
-  virtual void Initialize(VideoDecoder* decoder,
+  virtual void Initialize(const scoped_refptr<VideoDecoder>& decoder,
                           const PipelineStatusCB& status_cb,
                           const StatisticsCB& statistics_cb,
                           const TimeCB& time_cb) = 0;
@@ -180,7 +189,6 @@ class MEDIA_EXPORT VideoRenderer : public Filter {
   virtual bool HasEnded() = 0;
 };
 
-
 class MEDIA_EXPORT AudioRenderer : public Filter {
  public:
   // Used to update the pipeline's clock time. The first parameter is the