Moved creation of AudioDecoderFactory to inside PeerConnectionFactory.

webrtc/voice_engine/channel_proxy.cc

Index: webrtc/voice_engine/channel_proxy.cc
diff --git a/webrtc/voice_engine/channel_proxy.cc b/webrtc/voice_engine/channel_proxy.cc
index 4cc7f5cbbcdc61cd3f0c68481006ebb88703b4c4..d16167f9bb15bfff51e0be616531fd938a1c930c 100644
--- a/webrtc/voice_engine/channel_proxy.cc
+++ b/webrtc/voice_engine/channel_proxy.cc
@@ -181,6 +181,11 @@ bool ChannelProxy::ReceivedRTCPPacket(const uint8_t* packet, size_t length) {
   return channel()->ReceivedRTCPPacket(packet, length) == 0;
 }
 
+const rtc::scoped_refptr<AudioDecoderFactory>&
+ChannelProxy::GetAudioDecoderFactory() const {
+  return channel()->GetAudioDecoderFactory();
+}
+
 Channel* ChannelProxy::channel() const {
   RTC_DCHECK(channel_owner_.channel());
   return channel_owner_.channel();