Add UMA metrics for ICE regathering reasons.

webrtc/p2p/base/transportchannelimpl.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.
  */
 
 #ifndef WEBRTC_P2P_BASE_TRANSPORTCHANNELIMPL_H_
 #define WEBRTC_P2P_BASE_TRANSPORTCHANNELIMPL_H_
 
 #include <string>
 
 #include "webrtc/base/constructormagic.h"
 #include "webrtc/p2p/base/transportchannel.h"
 
 namespace buzz { class XmlElement; }
 
+namespace webrtc {
+class MetricsObserverInterface;
+}
+
 namespace cricket {
 
 class Candidate;
 
 // TODO(pthatcher): Remove this once it's no longer used in
 // remoting/protocol/libjingle_transport_factory.cc
 enum IceProtocolType {
   ICEPROTO_RFC5245  // Standard RFC 5245 version of ICE.
 };
 
@@ skipping 36 matching lines @@
 
   // SetRemoteIceMode must be implemented only by the ICE transport channels.
   virtual void SetRemoteIceMode(IceMode mode) = 0;
 
   virtual void SetIceConfig(const IceConfig& config) = 0;
 
   // Start gathering candidates if not already started, or if an ICE restart
   // occurred.
   virtual void MaybeStartGathering() = 0;
 
+  virtual void SetMetricsObserver(
+      webrtc::MetricsObserverInterface* observer) = 0;
+
   sigslot::signal1<TransportChannelImpl*> SignalGatheringState;
 
   // Handles sending and receiving of candidates.  The Transport
   // receives the candidates and may forward them to the relevant
   // channel.
   //
   // Note: Since candidates are delivered asynchronously to the
   // channel, they cannot return an error if the message is invalid.
   // It is assumed that the Transport will have checked validity
   // before forwarding.
@@ skipping 27 matching lines @@
   // Emitted whenever the Dtls handshake failed on some transport channel.
   sigslot::signal1<rtc::SSLHandshakeError> SignalDtlsHandshakeError;
 
  private:
   RTC_DISALLOW_COPY_AND_ASSIGN(TransportChannelImpl);
 };
 
 }  // namespace cricket
 
 #endif  // WEBRTC_P2P_BASE_TRANSPORTCHANNELIMPL_H_