Prevent a voice channel from sending data before a renderer is set.

webrtc/media/base/mediachannel.h

Index: webrtc/media/base/mediachannel.h
diff --git a/webrtc/media/base/mediachannel.h b/webrtc/media/base/mediachannel.h
index bab72b21926654ad0fb55c559787f717cdaf224c..71383d969d5c4b1ad8fc59fa3d718ac01e7cbada 100644
--- a/webrtc/media/base/mediachannel.h
+++ b/webrtc/media/base/mediachannel.h
@@ -42,7 +42,7 @@ class AudioSinkInterface;
 
 namespace cricket {
 
-class AudioRenderer;
+class AudioSource;
 class ScreencastId;
 class VideoCapturer;
 class VideoFrame;
@@ -906,7 +906,7 @@ class VoiceMediaChannel : public MediaChannel {
   virtual bool SetAudioSend(uint32_t ssrc,
                             bool enable,
                             const AudioOptions* options,
-                            AudioRenderer* renderer) = 0;
+                            AudioSource* source) = 0;
   // Gets current energy levels for all incoming streams.
   virtual bool GetActiveStreams(AudioInfo::StreamList* actives) = 0;
   // Get the current energy level of the stream sent to the speaker.