Move VideoDecoder initialization into VideoRendererBase.

media/base/pipeline.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef MEDIA_BASE_PIPELINE_H_
 #define MEDIA_BASE_PIPELINE_H_
 
 #include <string>
 
 #include "base/gtest_prod_util.h"
@@ skipping 13 matching lines @@
 class MessageLoopProxy;
 class TimeDelta;
 }
 
 namespace media {
 
 class AudioDecoder;
 class Clock;
 class FilterCollection;
 class MediaLog;
-class VideoDecoder;
 class VideoRenderer;
 
 // Adapter for using asynchronous Pipeline methods in code that wants to run
 // synchronously.  To use, construct an instance of this class and pass the
 // |Callback()| to the Pipeline method requiring a callback.  Then Wait() for
 // the callback to get fired and call status() to see what the callback's
 // argument was.  This object is for one-time use; call |Callback()| exactly
 // once.
 class MEDIA_EXPORT PipelineStatusNotification {
  public:
@@ skipping 162 matching lines @@
   // Only allow ourselves to be deleted by reference counting.
   friend class base::RefCountedThreadSafe<Pipeline>;
   virtual ~Pipeline();
 
   // Pipeline states, as described above.
   enum State {
     kCreated,
     kInitDemuxer,
     kInitAudioDecoder,
     kInitAudioRenderer,
-    kInitVideoDecoder,
     kInitVideoRenderer,
     kPausing,
     kSeeking,
     kFlushing,
     kStarting,
     kStarted,
     kStopping,
     kStopped,
   };
 
@@ skipping 117 matching lines @@
   // Internal methods used in the implementation of the pipeline thread.  All
   // of these methods are only called on the pipeline thread.
 
   // The following initialize methods are used to select a specific type of
   // object from FilterCollection and initialize it asynchronously.
   void InitializeDemuxer();
   void OnDemuxerInitialized(PipelineStatus status);
 
   // Returns true if the asynchronous action of creating decoder has started.
   // Returns false if this method did nothing because the corresponding
-  // audio/video stream does not exist.
+  // audio stream does not exist.
   bool InitializeAudioDecoder(const scoped_refptr<Demuxer>& demuxer);
-  bool InitializeVideoDecoder(const scoped_refptr<Demuxer>& demuxer);
 
   // Initializes a renderer and connects it with decoder. Returns true if the
   // asynchronous action of creating renderer has started. Returns
   // false if this method did nothing because the corresponding audio/video
   // stream does not exist.
   bool InitializeAudioRenderer(const scoped_refptr<AudioDecoder>& decoder);
-  bool InitializeVideoRenderer(const scoped_refptr<VideoDecoder>& decoder);
+  bool InitializeVideoRenderer(
+      const scoped_refptr<DemuxerStream>& stream);
 
   // Kicks off destroying filters. Called by StopTask() and ErrorChangedTask().
   // When we start to tear down the pipeline, we will consider two cases:
   // 1. when pipeline has not been initialized, we will transit to stopping
   // state first.
   // 2. when pipeline has been initialized, we will first transit to pausing
   // => flushing => stopping => stopped state.
   // This will remove the race condition during stop between filters.
   void TearDownPipeline();
 
@@ skipping 114 matching lines @@
 
   // Filter collection as passed in by Start().
   scoped_ptr<FilterCollection> filter_collection_;
 
   // Callbacks for various pipeline operations.
   PipelineStatusCB seek_cb_;
   base::Closure stop_cb_;
   PipelineStatusCB ended_cb_;
   PipelineStatusCB error_cb_;
 
-  // Decoder reference used for signalling imminent shutdown.
-  // This is a HACK necessary because WebMediaPlayerImpl::Destroy() holds the
-  // renderer thread loop hostage for until PipelineImpl::Stop() calls its
-  // callback.
-  // This reference should only be used for this hack and no other purposes.
-  // http://crbug.com/110228 tracks removing this hack.
-  scoped_refptr<VideoDecoder> video_decoder_;
-
-  // Renderer references used for setting the volume and determining
+  // Audio renderer reference used for setting the volume and determining
   // when playback has finished.
   scoped_refptr<AudioRenderer> audio_renderer_;
+
+  // Video Renderer reference used for determining when playback has finished

[scherkus (not reviewing), 2012/08/14 22:00:24]

this TODO isn't really applicable in this context anymore as we won't be
removing the video_renderer_ reference after that bug is fixed

I'd rather see this TODO by the ShutdownHack() method call / declaration

[acolwell GONE FROM CHROMIUM, 2012/08/15 21:36:57]

Ami asked me to keep the comment here
http://codereview.chromium.org/10836167/diff/7005/media/base/pipeline.h#newco...

+  // and for signalling imminent shutdown.
+  // The signalling imminent shutdown is a HACK necessary because
+  // WebMediaPlayerImpl::Destroy() holds the render thread loop hostage
+  // until PipelineImpl::Stop() calls its callback.
+  // http://crbug.com/110228 tracks removing this hack.
   scoped_refptr<VideoRenderer> video_renderer_;
 
   // Demuxer reference used for setting the preload value.
   scoped_refptr<Demuxer> demuxer_;
 
   // Helper class that stores filter references during pipeline
   // initialization.
   struct PipelineInitState;
   scoped_ptr<PipelineInitState> pipeline_init_state_;
 
   // Statistics.
   PipelineStatistics statistics_;
   // Time of pipeline creation; is non-zero only until the pipeline first
   // reaches "kStarted", at which point it is used & zeroed out.
   base::Time creation_time_;
 
   scoped_ptr<SerialRunner> pending_callbacks_;
 
   DISALLOW_COPY_AND_ASSIGN(Pipeline);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_PIPELINE_H_