Implement audio constraints for PeerConneciton API

content/renderer/media/media_stream_dependency_factory.cc

Index: content/renderer/media/media_stream_dependency_factory.cc
diff --git a/content/renderer/media/media_stream_dependency_factory.cc b/content/renderer/media/media_stream_dependency_factory.cc
index 8fb82a2596f139a504670bdc4785c3a70180a5c3..5a3870f9d6a9c350f067396354cafe7fda1de5ed 100644
--- a/content/renderer/media/media_stream_dependency_factory.cc
+++ b/content/renderer/media/media_stream_dependency_factory.cc
@@ -218,14 +218,15 @@ void MediaStreamDependencyFactory::CreateNativeMediaSources(
     const bool is_screencast = (source_data->device_info().device.type ==
         content::MEDIA_TAB_VIDEO_CAPTURE);
     source_data->SetVideoSource(
-        CreateVideoSource(source_data->device_info().session_id,
-                          is_screencast,
-                          &native_video_constraints));
+        CreateLocalVideoSource(source_data->device_info().session_id,
+                               is_screencast,
+                               &native_video_constraints));
     source_observer->AddSource(source_data->video_source());
   }
 
   // Do additional source initialization if the audio source is a valid
   // microphone or tab audio.
+  RTCMediaConstraints native_audio_constraints(audio_constraints);
   WebKit::WebVector<WebKit::WebMediaStreamComponent> audio_components;
   description->audioSources(audio_components);
   for (size_t i = 0; i < audio_components.size(); ++i) {
@@ -246,6 +247,11 @@ void MediaStreamDependencyFactory::CreateNativeMediaSources(
         return;
       }
     }
+
+    // Creates a LocalAudioSource object which holds audio options.
+    source_data->SetLocalAudioSource(
+        CreateLocalAudioSource(&native_audio_constraints));
+    source_observer->AddSource(source_data->local_audio_source());
   }
 
   source_observer->StartObservering();
@@ -276,10 +282,12 @@ void MediaStreamDependencyFactory::CreateNativeLocalMediaStream(
       // audio stream to each PeerConnection separately.  But currently WebRTC
       // is only able to handle a global audio stream sent to ALL peers.
 
-      // TODO(henrika): refactor and utilize audio constraints.
+      // TODO(henrika): Refactor and utilize audio constraints. Audio
+      // constraints are passed via LocalAudioSource.
       if (CreateWebAudioSource(&source)) {
         scoped_refptr<webrtc::LocalAudioTrackInterface> audio_track(
-            CreateLocalAudioTrack(UTF16ToUTF8(audio_components[i].id()), NULL));
+            CreateLocalAudioTrack(UTF16ToUTF8(audio_components[i].id()),
+                                  NULL));
         native_stream->AddTrack(audio_track);
         audio_track->set_enabled(audio_components[i].isEnabled());
       } else {
@@ -296,11 +304,9 @@ void MediaStreamDependencyFactory::CreateNativeLocalMediaStream(
           continue;
         }
 
-        // TODO(perkj): Refactor the creation of audio tracks to use a proper
-        // interface for receiving audio input data. Currently NULL is passed
-        // since the |audio_device| is the wrong class and is unused.
         scoped_refptr<webrtc::LocalAudioTrackInterface> audio_track(
-            CreateLocalAudioTrack(UTF16ToUTF8(source.id()), NULL));
+            CreateLocalAudioTrack(UTF16ToUTF8(source.id()),
+                                  source_data->local_audio_source()));
         native_stream->AddTrack(audio_track);
         audio_track->set_enabled(audio_components[i].isEnabled());
     }
@@ -386,8 +392,16 @@ MediaStreamDependencyFactory::CreateLocalMediaStream(
   return pc_factory_->CreateLocalMediaStream(label).get();
 }
 
+scoped_refptr<webrtc::AudioSourceInterface>
+MediaStreamDependencyFactory::CreateLocalAudioSource(
+    const webrtc::MediaConstraintsInterface* constraints) {
+  scoped_refptr<webrtc::AudioSourceInterface> source =
+      pc_factory_->CreateAudioSource(constraints).get();
+  return source;
+}
+
 scoped_refptr<webrtc::VideoSourceInterface>
-MediaStreamDependencyFactory::CreateVideoSource(
+MediaStreamDependencyFactory::CreateLocalVideoSource(
     int video_session_id,
     bool is_screencast,
     const webrtc::MediaConstraintsInterface* constraints) {
@@ -459,8 +473,8 @@ MediaStreamDependencyFactory::CreateLocalVideoTrack(
 scoped_refptr<webrtc::LocalAudioTrackInterface>
 MediaStreamDependencyFactory::CreateLocalAudioTrack(
     const std::string& label,
-    webrtc::AudioDeviceModule* audio_device) {
-  return pc_factory_->CreateLocalAudioTrack(label, audio_device).get();
+    webrtc::AudioSourceInterface* source) {
+  return pc_factory_->CreateAudioTrack(label, source).get();
 }
 
 webrtc::SessionDescriptionInterface*