Fix erratic HTML5 audio playback

media/audio/audio_output_dispatcher.h

 // Copyright (c) 2011 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.
 
 // AudioOutputDispatcher dispatches creation and deletion of audio
 // output streams. AudioOutputProxy objects use this class to allocate
 // and recycle actual audio output streams. When playback is started,
 // the proxy calls StreamStarted() to get an output stream that it
 // uses to play the sound. When playback is stopped, the proxy returns
 // the stream back to the dispatcher by calling StreamStopped().
 //
 // To avoid opening and closing audio devices more frequently than it
 // is neccessary, each dispatcher has a pool of inactive physical
 // streams. A stream is closed only if it hasn't been used for a
 // certain period of time (specified in the constructor).
 //
 // AudioManagerBase creates one AudioOutputDispatcher per each
 // possible set of audio parameters, i.e. streams with different
 // parameters are managed independently.
 
 #ifndef MEDIA_AUDIO_AUDIO_OUTPUT_DISPATCHER_H_
 #define MEDIA_AUDIO_AUDIO_OUTPUT_DISPATCHER_H_
 
 #include <vector>
+#include <list>

[scherkus (not reviewing), 2011/04/11 22:32:33]

nit: list comes before vector

 
 #include "base/basictypes.h"
 #include "base/memory/ref_counted.h"
 #include "base/timer.h"
 #include "media/audio/audio_manager.h"
 #include "media/audio/audio_parameters.h"
 
 class AudioOutputStream;
 class MessageLoop;
 
@@ skipping 34 matching lines @@
 
   // Creates a new physical output stream, opens it and pushes to
   // |streams_|.  Returns false if the stream couldn't be created or
   // opened.
   bool CreateAndOpenStream();
 
   // A task scheduled by StreamStarted(). Opens a new stream and puts
   // it in |streams_|.
   void OpenTask();
 
+  // Before a stream is reused, it should sit idle for a bit.  This task is
+  // called once that time has elapsed.
+  void StopStreamTask();
+
   // Called by |close_timer_|. Closes all pending stream.
   void ClosePendingStreams();
 
   AudioManager* audio_manager_;
   MessageLoop* message_loop_;
   AudioParameters params_;
 
   size_t paused_proxies_;
   std::vector<AudioOutputStream*> streams_;
+  std::list<AudioOutputStream*> idle_streams_;

[Sergey Ulanov, 2011/04/09 07:02:05]

Please add comments that explain difference between streams_ and idle_streams_.
I'm not sure if idle_streams_ is a good name. Maybe call it pausing_streams_,
and rename streams_ to idle_streams_, to show the difference? In that case we
would not need a comment.

   base::DelayTimer<AudioOutputDispatcher> close_timer_;
 
   DISALLOW_COPY_AND_ASSIGN(AudioOutputDispatcher);
 };
 
 #endif  // MEDIA_AUDIO_AUDIO_OUTPUT_DISPATCHER_H_