Build WebRTC with data channel only.

webrtc/media/base/codec.cc

Index: webrtc/media/base/codec.cc
diff --git a/webrtc/media/base/codec.cc b/webrtc/media/base/codec.cc
index 1e305a60b71369e41b797e6b388f15b33f0f7438..7da1de69033151b6724930d36dd92db765b948f8 100644
--- a/webrtc/media/base/codec.cc
+++ b/webrtc/media/base/codec.cc
@@ -23,6 +23,7 @@ namespace cricket {
 
 static bool IsSameH264Profile(const CodecParameterMap& params1,
                               const CodecParameterMap& params2) {
+#if defined(HAVE_WEBRTC_VOICE) && defined(HAVE_WEBRTC_VIDEO)

[Taylor Brandstetter, 2017/05/11 04:43:11]

Only need HAVE_WEBRTC_VIDEO, technically

[Zhi Huang, 2017/05/12 20:05:33]

Done.

   const rtc::Optional<webrtc::H264::ProfileLevelId> profile_level_id =
       webrtc::H264::ParseSdpProfileLevelId(params1);
   const rtc::Optional<webrtc::H264::ProfileLevelId> other_profile_level_id =
@@ -30,6 +31,9 @@ static bool IsSameH264Profile(const CodecParameterMap& params1,
   // Compare H264 profiles, but not levels.
   return profile_level_id && other_profile_level_id &&
          profile_level_id->profile == other_profile_level_id->profile;
+#else
+  return false;

[Taylor Brandstetter, 2017/05/11 04:43:11]

In all of these "#else" blocks, can you add RTC_NOTREACHED, since this code is
never expected to be hit?

[Zhi Huang, 2017/05/12 20:05:33]

Done.

+#endif
 }
 
 bool FeedbackParam::operator==(const FeedbackParam& other) const {