Implement Turn/Turn first logic for connection selection.

webrtc/p2p/base/transport.h

Index: webrtc/p2p/base/transport.h
diff --git a/webrtc/p2p/base/transport.h b/webrtc/p2p/base/transport.h
index 6b4b37d4c56b89e0abc9617ff58b1fc92d96170e..18aa59ae0d4177bbf32860caaa7a1e892c9ae6bb 100644
--- a/webrtc/p2p/base/transport.h
+++ b/webrtc/p2p/base/transport.h
@@ -147,6 +147,7 @@ struct IceConfig {
   int backup_connection_ping_interval = -1;
   // If true, the most recent port allocator session will keep on running.
   bool gather_continually = false;
+  bool ping_most_likely_candidate_pair_first = false;

[pthatcher1, 2016/01/27 19:59:59]

And here, the name could be the same but without "ice" in it:
prioritize_most_likely_candidate_pairs

[guoweis_webrtc, 2016/02/29 18:03:01]

Done.

 };
 
 bool BadTransportDescription(const std::string& desc, std::string* err_desc);