Build WebRTC with data channel only.

webrtc/pc/channel_audio.cc

Index: webrtc/pc/channel_audio.cc
diff --git a/webrtc/pc/channel_audio.cc b/webrtc/pc/channel_audio.cc
new file mode 100644
index 0000000000000000000000000000000000000000..8224be680f3015cd4141cee9ef882ddb5247cca9
--- /dev/null
+++ b/webrtc/pc/channel_audio.cc
@@ -0,0 +1,21 @@
+/*
+ *  Copyright 2017 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.
+ */
+
+#include "webrtc/api/rtpreceiverinterface.h"
+#include "webrtc/media/engine/webrtcvoiceengine.h"
+
+namespace cricket {
+
+std::vector<webrtc::RtpSource> GetSourcesImpl(
+    WebRtcVoiceMediaChannel* media_channel,
+    uint32_t ssrc) {
+  return media_channel->GetSources(ssrc);
+}

[pthatcher, 2017/05/18 17:50:26]

Why not stick this in audiofactory.cc?

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

I'll remove this file.

+}  // namespace cricket