Implements the GetSignalLevel and GetStats interface for the local audio track.

content/renderer/media/webrtc_local_audio_track.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 "content/renderer/media/webrtc_local_audio_track.h"
 
 #include "content/public/renderer/media_stream_audio_sink.h"
 #include "content/renderer/media/media_stream_audio_level_calculator.h"
+#include "content/renderer/media/media_stream_audio_processor.h"
 #include "content/renderer/media/media_stream_audio_sink_owner.h"
 #include "content/renderer/media/media_stream_audio_track_sink.h"
 #include "content/renderer/media/peer_connection_audio_sink_owner.h"
 #include "content/renderer/media/webaudio_capturer_source.h"
 #include "content/renderer/media/webrtc/webrtc_local_audio_track_adapter.h"
 #include "content/renderer/media/webrtc_audio_capturer.h"
 
 namespace content {
 
 WebRtcLocalAudioTrack::WebRtcLocalAudioTrack(
@@ skipping 87 matching lines @@
   DCHECK(capture_thread_checker_.CalledOnValidThread());
 
   audio_parameters_ = params;
   level_calculator_.reset(new MediaStreamAudioLevelCalculator());
 
   base::AutoLock auto_lock(lock_);
   // Remember to notify all sinks of the new format.
   sinks_.TagAll();
 }
 
+void WebRtcLocalAudioTrack::SetAudioProcessor(
+    const scoped_refptr<MediaStreamAudioProcessor>& processor) {
+  // if the |processor| does not have audio processing, which can happen if
+  // kEnableAudioTrackProcessing is not set or all the constraints in
+  // the |processor| are turned off. In such case, we pass NULL to the
+  // adapter to indicate that no stats can be gotten from the processor.
+  if (processor->has_audio_processing())
+    adapter_->SetAudioProcessor(processor.get());
+  else
+    adapter_->SetAudioProcessor(NULL);

[tommi (sloooow) - chröme, 2014/03/04 17:33:54]

nit: for fewer call sites and less code:
adapter_->SetAudioProcessor(
    processor->has_audio_processing() ? processor.get() : NULL);

also, if you change SetAudioProcessor to use chrome's scoped_refptr, you won't
need the call to .get().

[no longer working on chromium, 2014/03/04 18:54:07]

Done.

+}
+
 void WebRtcLocalAudioTrack::AddSink(MediaStreamAudioSink* sink) {
   DCHECK(main_render_thread_checker_.CalledOnValidThread());
   DVLOG(1) << "WebRtcLocalAudioTrack::AddSink()";
   base::AutoLock auto_lock(lock_);
 
   // Verify that |sink| is not already added to the list.
   DCHECK(!sinks_.Contains(
       MediaStreamAudioTrackSink::WrapsMediaStreamSink(sink)));
 
   // Create (and add to the list) a new MediaStreamAudioTrackSink
@@ skipping 109 matching lines @@
 
   for (SinkList::ItemList::const_iterator it = sinks.begin();
        it != sinks.end();
        ++it){
     (*it)->OnReadyStateChanged(blink::WebMediaStreamSource::ReadyStateEnded);
     (*it)->Reset();
   }
 }
 
 }  // namespace content