Removing DataSource from Filter hierarchy

media/base/demuxer.h

Index: media/base/demuxer.h
diff --git a/media/base/demuxer.h b/media/base/demuxer.h
index 972d250a094cfdbd84d275718d3b837edaa4c15c..f049f6f49cafa038d33d7ae50c7ed5ad2b0b5381 100644
--- a/media/base/demuxer.h
+++ b/media/base/demuxer.h
@@ -6,28 +6,45 @@
 #define MEDIA_BASE_DEMUXER_H_
 
 #include "base/memory/ref_counted.h"
+#include "base/time.h"
+#include "media/base/data_source.h"
 #include "media/base/demuxer_stream.h"
 #include "media/base/media_export.h"
-
-// TODO(acolwell): Remove include once DataSource & Preload are moved
-// out of "media/base/filters.h" and Stop() is converted to use new callbacks.
-#include "media/base/filters.h"
 #include "media/base/pipeline_status.h"
+#include "media/base/preload.h"
 
 namespace media {
 
-class FilterHost;
+class MEDIA_EXPORT DemuxerHost : public DataSourceHost {
+ public:
+  virtual ~DemuxerHost();
+
+  // Get the duration of the media in microseconds.  If the duration has not
+  // been determined yet, then returns 0.
+  virtual void SetDuration(base::TimeDelta duration) = 0;
+
+  // Set the approximate amount of playable data buffered so far in micro-
+  // seconds.
+  virtual void SetBufferedTime(base::TimeDelta buffered_time) = 0;
+
+  // Sets the byte offset at which the client is requesting the video.
+  virtual void SetCurrentReadPosition(int64 offset) = 0;
+
+  // Stops execution of the pipeline due to a fatal error.  Do not call this
+  // method with PIPELINE_OK.
+  virtual void OnDemuxerError(PipelineStatus error) = 0;
+};
 
 class MEDIA_EXPORT Demuxer
     : public base::RefCountedThreadSafe<Demuxer> {
  public:
+  Demuxer();
+
   // Sets the private member |host_|. This is the first method called by
-  // the FilterHost after a demuxer is created.  The host holds a strong
+  // the DemuxerHost after a demuxer is created.  The host holds a strong
   // reference to the demuxer.  The reference held by the host is guaranteed
   // to be released before the host object is destroyed by the pipeline.
-  //
-  // TODO(acolwell): Change this to a narrow DemuxerHost interface.
-  virtual void set_host(FilterHost* host);
+  virtual void set_host(DemuxerHost* host);
 
   // The pipeline playback rate has been changed.  Demuxers may implement this
   // method if they need to respond to this call.
@@ -69,14 +86,18 @@ class MEDIA_EXPORT Demuxer
   virtual bool IsSeekable() = 0;
 
  protected:
-  Demuxer();
-  FilterHost* host() { return host_; }
+  // Only allow derived objects access to the DemuxerHost. This is
+  // kept out of the public interface because demuxers need to be
+  // aware of all calls made to the host object so they can insure
+  // the state presented to the host is always consistent with its own
+  // state.
+  DemuxerHost* host() { return host_; }
 
   friend class base::RefCountedThreadSafe<Demuxer>;
   virtual ~Demuxer();
 
  private:
-  FilterHost* host_;
+  DemuxerHost* host_;
 
   DISALLOW_COPY_AND_ASSIGN(Demuxer);
 };