Clean up the media stream audio track code

content/renderer/media/webrtc/webrtc_local_audio_track_adapter.cc

 // Copyright 2014 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 "content/renderer/media/webrtc/webrtc_local_audio_track_adapter.h"
 
 #include "base/logging.h"
 #include "content/renderer/media/media_stream_audio_processor.h"
 #include "content/renderer/media/webrtc/peer_connection_dependency_factory.h"
 #include "content/renderer/media/webrtc/webrtc_audio_sink_adapter.h"
@@ skipping 109 matching lines @@
       owner_->RemoveSink(*it);
       sink_adapters_.erase(it);
       return;
     }
   }
 }
 
 bool WebRtcLocalAudioTrackAdapter::GetSignalLevel(int* level) {
   DCHECK(signaling_thread_checker_.CalledOnValidThread());
 
-  // It is required to provide the signal level after audio processing. In
-  // case the audio processing is not enabled for the track, we return
-  // false here in order not to overwrite the value from WebRTC.
-  // TODO(xians): Remove this after we turn on the APM in Chrome by default.
-  // http://crbug/365672 .
-  if (!MediaStreamAudioProcessor::IsAudioTrackProcessingEnabled())
-    return false;
-
   base::AutoLock auto_lock(lock_);
   *level = signal_level_;
   return true;
 }
 
 rtc::scoped_refptr<webrtc::AudioProcessorInterface>
 WebRtcLocalAudioTrackAdapter::GetAudioProcessor() {
   DCHECK(signaling_thread_checker_.CalledOnValidThread());
   base::AutoLock auto_lock(lock_);
   return audio_processor_.get();
@@ skipping 36 matching lines @@
   DCHECK(iter != voe_channels_.end());
   voe_channels_.erase(iter);
 }
 
 webrtc::AudioSourceInterface* WebRtcLocalAudioTrackAdapter::GetSource() const {
   DCHECK(signaling_thread_checker_.CalledOnValidThread());
   return track_source_;
 }
 
 cricket::AudioRenderer* WebRtcLocalAudioTrackAdapter::GetRenderer() {
-  // When the audio track processing is enabled, return a NULL so that capture
-  // data goes through Libjingle LocalAudioTrackHandler::LocalAudioSinkAdapter
-  // ==> WebRtcVoiceMediaChannel::WebRtcVoiceChannelRenderer ==> WebRTC.
-  // When the audio track processing is disabled, WebRtcLocalAudioTrackAdapter
-  // is used to pass the channel ids to WebRtcAudioDeviceImpl, the data flow
-  // becomes WebRtcAudioDeviceImpl ==> WebRTC.
-  // TODO(xians): Only return NULL after the APM in WebRTC is deprecated.
-  // See See http://crbug/365672 for details.
-  return MediaStreamAudioProcessor::IsAudioTrackProcessingEnabled()?
-      NULL : this;
+  return NULL;
 }
 
 }  // namespace content