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

webrtc/pc/channel.cc

Index: webrtc/pc/channel.cc
diff --git a/webrtc/pc/channel.cc b/webrtc/pc/channel.cc
index 1d5d159d05fd786eafc6fb909fb96298d64e3c52..e64db76fa0dca8a1b077c0691774c2e6c0d66a78 100644
--- a/webrtc/pc/channel.cc
+++ b/webrtc/pc/channel.cc
@@ -1342,9 +1342,9 @@ bool VoiceChannel::Init() {
 bool VoiceChannel::SetAudioSend(uint32_t ssrc,
                                 bool enable,
                                 const AudioOptions* options,
-                                AudioRenderer* renderer) {
+                                AudioSource* source) {
   return InvokeOnWorker(Bind(&VoiceMediaChannel::SetAudioSend, media_channel(),
-                             ssrc, enable, options, renderer));
+                             ssrc, enable, options, source));
 }
 
 // TODO(juberti): Handle early media the right way. We should get an explicit