Require Renderer::Initialize() to return a status code via callback.

media/base/video_renderer.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_VIDEO_RENDERER_H_
 #define MEDIA_BASE_VIDEO_RENDERER_H_
 
 #include "base/callback.h"
 #include "base/memory/ref_counted.h"
 #include "base/time/time.h"
@@ skipping 15 matching lines @@
 
   // Used to query the current time or duration of the media.
   typedef base::Callback<base::TimeDelta()> TimeDeltaCB;
 
   VideoRenderer();
 
   // Stops all operations and fires all pending callbacks.
   virtual ~VideoRenderer();
 
   // Initializes a VideoRenderer with |stream|, executing |init_cb| upon
-  // completion.
+  // completion. If initialization fails, only |init_cb| (not |error_cb|) will
+  // be called.
   //
   // |set_decryptor_ready_cb| is fired when a Decryptor is needed, i.e. when the
   // |stream| is encrypted.
   //
   // |statistics_cb| is executed periodically with video rendering stats, such
   // as dropped frames.
   //
   // |buffering_state_cb| is executed when video rendering has either run out of
   // data or has enough data to continue playback.
   //
   // |paint_cb| is executed on the video frame timing thread whenever a new
   // frame is available for painting. Can be called from any thread.
   //
   // |ended_cb| is executed when video rendering has reached the end of stream.
   //
-  // |error_cb| is executed if an error was encountered.
+  // |error_cb| is executed if an error was encountered after initialization.
   //
   // |get_time_cb| is used to query the current media playback time.
   virtual void Initialize(DemuxerStream* stream,
                           const PipelineStatusCB& init_cb,
                           const SetDecryptorReadyCB& set_decryptor_ready_cb,
                           const StatisticsCB& statistics_cb,
                           const BufferingStateCB& buffering_state_cb,
                           const PaintCB& paint_cb,
                           const base::Closure& ended_cb,
                           const PipelineStatusCB& error_cb,
@@ skipping 12 matching lines @@
   // Only valid to call after a successful Initialize() or Flush().
   virtual void StartPlayingFrom(base::TimeDelta timestamp) = 0;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(VideoRenderer);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_VIDEO_RENDERER_H_