Using AudioOption to enable audio network adaptor.

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 ba58502e956c4e3105545b9d2bfd939862f42ecf..07b2b89b5756cfddcedca3cfeeec592aa1baa812 100644
--- a/webrtc/voice_engine/channel_proxy.cc
+++ b/webrtc/voice_engine/channel_proxy.cc
@@ -214,6 +214,23 @@ void ChannelProxy::SetRtcEventLog(RtcEventLog* event_log) {
   channel()->SetRtcEventLog(event_log);
 }
 
+bool ChannelProxy::EnableAudioNetworkAdaptor(const std::string& config_string) {
+  RTC_DCHECK(thread_checker_.CalledOnValidThread());
+  return channel()->EnableAudioNetworkAdaptor(config_string);

[the sun, 2016/10/28 18:21:52]

AFAICT this call cannot fail (that would mean new() failed for
AudioNetworkAdaptorImpl). Please remove the return value in the ChannelProxy and
DCHECK the assumption instead. Preferably, you could also create a CL to
simplify things down the chain - I don't see how this settable
NetworkAdaptorCreator is ever used - only the default one seems to be used?

[minyue-webrtc, 2016/10/28 18:41:57]

I see. I can remove return value and DCHECH result from channel here in this CL.

General question: do we plan to add a CreateAudioSendStream which gives nullptr
or failure info when creation is failed?

[the sun, 2016/10/28 19:04:47]

sgtm
That's a good question. Currently, the answer is 'no', no such plans. This is
pretty deep subject. Personally I think return codes should only be used when
there's a possibility for resource exhaustion (e.g. some piece of hardware or OS
function cannot be accessed) AND the API client can conceivably use the return
code to work around it. RAM is obviously a hardware resources, but one that we
depend on throughout the stack to such a large extent that, if we'd run out,
we'd already be in deep trouble and might as well terminate the process.

So, for most things we do, where RAM is the only resource requirement, return
codes are not that useful.

+}
+
+void ChannelProxy::DisableAudioNetworkAdaptor() {
+  RTC_DCHECK(thread_checker_.CalledOnValidThread());
+  channel()->DisableAudioNetworkAdaptor();
+}
+
+void ChannelProxy::SetReceiverFrameLengthRange(int min_frame_length_ms,
+                                               int max_frame_length_ms) {
+  RTC_DCHECK(thread_checker_.CalledOnValidThread());
+  channel()->SetReceiverFrameLengthRange(min_frame_length_ms,
+                                         max_frame_length_ms);
+}
+
 AudioMixer::Source::AudioFrameInfo ChannelProxy::GetAudioFrameWithInfo(
     int sample_rate_hz,
     AudioFrame* audio_frame) {