Only try to pair protocol matching candidates for creating connections.

webrtc/p2p/base/stunport.h

 /*
  *  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 77 matching lines @@
   virtual int GetError();
 
   virtual bool HandleIncomingPacket(
       rtc::AsyncPacketSocket* socket, const char* data, size_t size,
       const rtc::SocketAddress& remote_addr,
       const rtc::PacketTime& packet_time) {
     // All packets given to UDP port will be consumed.
     OnReadPacket(socket, data, size, remote_addr, packet_time);
     return true;
   }
+  virtual bool SupportsProtocol(const std::string& protocol) const {
+    return protocol == UDP_PROTOCOL_NAME;
+  }
 
   void set_stun_keepalive_delay(int delay) {
     stun_keepalive_delay_ = delay;
   }
   int stun_keepalive_delay() const {
     return stun_keepalive_delay_;
   }
 
  protected:
   UDPPort(rtc::Thread* thread,
@@ skipping 166 matching lines @@
                 false) {
     // UDPPort will set these to local udp, updating these to STUN.
     set_type(STUN_PORT_TYPE);
     set_server_addresses(servers);
   }
 };
 
 }  // namespace cricket
 
 #endif  // WEBRTC_P2P_BASE_STUNPORT_H_