Add logging of host lookups made by TurnPort to the RtcEventLog.

webrtc/rtc_base/asyncresolverinterface.h

 /*
  *  Copyright 2013 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 19 matching lines @@
   virtual int GetError() const = 0;
   // Delete the resolver.
   virtual void Destroy(bool wait) = 0;
   // Returns top most resolved IPv4 address if address is resolved successfully.
   // Otherwise returns address set in SetAddress.
   SocketAddress address() const {
     SocketAddress addr;
     GetResolvedAddress(AF_INET, &addr);
     return addr;
   }
+  virtual int64_t GetResolveElapsedTimeMilliseconds() const = 0;
 
   // This signal is fired when address resolve process is completed.
   sigslot::signal1<AsyncResolverInterface*> SignalDone;
 };
 
 }  // namespace rtc
 
 #endif