media: Introduce Renderer interface and RendererImpl.

media/filters/audio_renderer_impl.cc

 // 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.
 
 #include "media/filters/audio_renderer_impl.h"
 
 #include <math.h>
 
 #include <algorithm>
 
@@ skipping 240 matching lines @@
   DCHECK(!statistics_cb.is_null());
   DCHECK(!time_cb.is_null());
   DCHECK(!buffering_state_cb.is_null());
   DCHECK(!ended_cb.is_null());
   DCHECK(!error_cb.is_null());
   DCHECK_EQ(kUninitialized, state_);
   DCHECK(sink_);
 
   state_ = kInitializing;
 
-  init_cb_ = init_cb;
+  // Always post |init_cb_| because |this| could be destroyed if initialization
+  // failed.
+  init_cb_ = BindToCurrentLoop(init_cb);
+
   time_cb_ = time_cb;
   buffering_state_cb_ = buffering_state_cb;
   ended_cb_ = ended_cb;
   error_cb_ = error_cb;
 
   expecting_config_changes_ = stream->SupportsConfigChanges();
   if (!expecting_config_changes_) {
     // The actual buffer size is controlled via the size of the AudioBus
     // provided to Render(), so just choose something reasonable here for looks.
     int buffer_size = stream->audio_decoder_config().samples_per_second() / 100;
@@ skipping 69 matching lines @@
   {
     base::AutoUnlock auto_unlock(lock_);
     sink_->Initialize(audio_parameters_, this);
     sink_->Start();
 
     // Some sinks play on start...
     sink_->Pause();
   }
 
   DCHECK(!sink_playing_);
-
   base::ResetAndReturn(&init_cb_).Run(PIPELINE_OK);
 }
 
 void AudioRendererImpl::SetVolume(float volume) {
   DCHECK(task_runner_->BelongsToCurrentThread());
   DCHECK(sink_);
   sink_->SetVolume(volume);
 }
 
 void AudioRendererImpl::DecodedAudioReady(
@@ skipping 337 matching lines @@
            << buffering_state;
   DCHECK_NE(buffering_state_, buffering_state);
   lock_.AssertAcquired();
   buffering_state_ = buffering_state;
 
   task_runner_->PostTask(FROM_HERE,
                          base::Bind(buffering_state_cb_, buffering_state_));
 }
 
 }  // namespace media