Add the URL attribute to cricket::Candiate.

webrtc/p2p/base/stunport.cc

Index: webrtc/p2p/base/stunport.cc
diff --git a/webrtc/p2p/base/stunport.cc b/webrtc/p2p/base/stunport.cc
index be844d54dc4bd8d0f72759471da831e4737206ef..5072ffc73a3b48765edea6229d6b6d81896b4306 100644
--- a/webrtc/p2p/base/stunport.cc
+++ b/webrtc/p2p/base/stunport.cc
@@ -315,7 +315,7 @@ void UDPPort::OnLocalAddressReady(rtc::AsyncPacketSocket* socket,
   MaybeSetDefaultLocalAddress(&addr);
 
   AddAddress(addr, addr, rtc::SocketAddress(), UDP_PROTOCOL_NAME, "", "",
-             LOCAL_PORT_TYPE, ICE_TYPE_PREFERENCE_HOST, 0, false);
+             LOCAL_PORT_TYPE, ICE_TYPE_PREFERENCE_HOST, 0, "", false);
   MaybePrepareStunCandidate();
 }
 
@@ -453,9 +453,10 @@ void UDPPort::OnStunBindingRequestSucceeded(
           related_address.family());
     }
 
+    std::string url = "stun:" + stun_server_addr.ToString();
     AddAddress(stun_reflected_addr, socket_->GetLocalAddress(), related_address,
                UDP_PROTOCOL_NAME, "", "", STUN_PORT_TYPE,
-               ICE_TYPE_PREFERENCE_SRFLX, 0, false);
+               ICE_TYPE_PREFERENCE_SRFLX, 0, url, false);
   }
   MaybeSetPortCompleteOrError();
 }