Build WebRTC with data channel only.

webrtc/pc/peerconnectionfactory.cc

 /*
  *  Copyright 2004 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 19 matching lines @@
 #include "webrtc/p2p/client/basicportallocator.h"
 #include "webrtc/pc/audiotrack.h"
 #include "webrtc/pc/localaudiosource.h"
 #include "webrtc/pc/mediastream.h"
 #include "webrtc/pc/peerconnection.h"
 #include "webrtc/pc/videocapturertracksource.h"
 #include "webrtc/pc/videotrack.h"
 
 namespace webrtc {
 
+rtc::scoped_refptr<AudioEncoderFactory> CreateBuiltinAudioEncoderFactoryImpl();
+
+rtc::scoped_refptr<AudioDecoderFactory> CreateBuiltinAudioDecoderFactoryImpl();
+
+std::unique_ptr<cricket::MediaEngineInterface> CreateMediaEngineImpl(
+    webrtc::AudioDeviceModule* adm,
+    const rtc::scoped_refptr<webrtc::AudioEncoderFactory>&
+        audio_encoder_factory,
+    const rtc::scoped_refptr<webrtc::AudioDecoderFactory>&
+        audio_decoder_factory,
+    cricket::WebRtcVideoEncoderFactory* video_encoder_factory,
+    cricket::WebRtcVideoDecoderFactory* video_decoder_factory,
+    rtc::scoped_refptr<webrtc::AudioMixer> audio_mixer);

[Taylor Brandstetter, 2017/05/18 17:57:05]

Are the extra "Impl" methods needed here? It seems like the "nullimpl.cc" files
could just implement CreateBuiltinAudioEncoderFactory,
CreateBuiltinAudioDecoderFactory and WebRtcMediaEngineFactory::Create directly.

And actually, same for CreateCallImpl and Call::Create.

[Zhi Huang, 2017/05/23 03:40:35]

I think we still need CreateBuiltinAudioEncoderFactoryImpl otherwise this method
would be define twice and we can't just remove the old one since chromium is
depending on it.

I'll remove others.

+
 rtc::scoped_refptr<PeerConnectionFactoryInterface> CreatePeerConnectionFactory(
     rtc::scoped_refptr<AudioEncoderFactory> audio_encoder_factory,
     rtc::scoped_refptr<AudioDecoderFactory> audio_decoder_factory) {
   rtc::scoped_refptr<PeerConnectionFactory> pc_factory(
       new rtc::RefCountedObject<PeerConnectionFactory>(audio_encoder_factory,
                                                        audio_decoder_factory));
 
   RTC_CHECK(rtc::Thread::Current() == pc_factory->signaling_thread());
   // The signaling thread is the current thread so we can
   // safely call Initialize directly.
   if (!pc_factory->Initialize()) {
     return nullptr;
   }
   return PeerConnectionFactoryProxy::Create(pc_factory->signaling_thread(),
                                             pc_factory);
 }
 
 rtc::scoped_refptr<PeerConnectionFactoryInterface>
 CreatePeerConnectionFactory() {
-  return CreatePeerConnectionFactory(CreateBuiltinAudioEncoderFactory(),
-                                     CreateBuiltinAudioDecoderFactory());
+  return CreatePeerConnectionFactory(CreateBuiltinAudioEncoderFactoryImpl(),
+                                     CreateBuiltinAudioDecoderFactoryImpl());
 }
 
 rtc::scoped_refptr<PeerConnectionFactoryInterface> CreatePeerConnectionFactory(
     rtc::Thread* network_thread,
     rtc::Thread* worker_thread,
     rtc::Thread* signaling_thread,
     AudioDeviceModule* default_adm,
     rtc::scoped_refptr<AudioEncoderFactory> audio_encoder_factory,
     rtc::scoped_refptr<AudioDecoderFactory> audio_decoder_factory,
     cricket::WebRtcVideoEncoderFactory* video_encoder_factory,
@@ skipping 49 matching lines @@
 CreatePeerConnectionFactoryWithAudioMixer(
     rtc::Thread* network_thread,
     rtc::Thread* worker_thread,
     rtc::Thread* signaling_thread,
     AudioDeviceModule* default_adm,
     cricket::WebRtcVideoEncoderFactory* encoder_factory,
     cricket::WebRtcVideoDecoderFactory* decoder_factory,
     rtc::scoped_refptr<AudioMixer> audio_mixer) {
   return CreatePeerConnectionFactoryWithAudioMixer(
       network_thread, worker_thread, signaling_thread, default_adm,
-      CreateBuiltinAudioEncoderFactory(), CreateBuiltinAudioDecoderFactory(),
-      encoder_factory, decoder_factory, audio_mixer);
+      CreateBuiltinAudioEncoderFactoryImpl(),
+      CreateBuiltinAudioDecoderFactoryImpl(), encoder_factory, decoder_factory,
+      audio_mixer);
 }
 
 PeerConnectionFactory::PeerConnectionFactory(
     rtc::scoped_refptr<webrtc::AudioEncoderFactory> audio_encoder_factory,
     rtc::scoped_refptr<webrtc::AudioDecoderFactory> audio_decoder_factory)
     : owns_ptrs_(true),
       wraps_current_thread_(false),
       network_thread_(rtc::Thread::CreateWithSocketServer().release()),
       worker_thread_(rtc::Thread::Create().release()),
       signaling_thread_(rtc::Thread::Current()),
@@ skipping 236 matching lines @@
   return worker_thread_;
 }
 
 rtc::Thread* PeerConnectionFactory::network_thread() {
   return network_thread_;
 }
 
 std::unique_ptr<cricket::MediaEngineInterface>
 PeerConnectionFactory::CreateMediaEngine_w() {
   RTC_DCHECK(worker_thread_ == rtc::Thread::Current());
-  return std::unique_ptr<cricket::MediaEngineInterface>(
-      cricket::WebRtcMediaEngineFactory::Create(
-          default_adm_.get(), audio_encoder_factory_,
-          audio_decoder_factory_,
-          video_encoder_factory_.get(), video_decoder_factory_.get(),
-          external_audio_mixer_));
+  return CreateMediaEngineImpl(
+      default_adm_.get(), audio_encoder_factory_, audio_decoder_factory_,
+      video_encoder_factory_.get(), video_decoder_factory_.get(),
+      external_audio_mixer_);
 }
 
 }  // namespace webrtc