Add the last_sent_packet_id to the candidate pair change signal

webrtc/p2p/base/p2ptransportchannel.cc

 /*
  *  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 965 matching lines @@
   ASSERT(worker_thread_ == rtc::Thread::Current());
   if (flags != 0) {
     error_ = EINVAL;
     return -1;
   }
   if (best_connection_ == NULL) {
     error_ = EWOULDBLOCK;
     return -1;
   }
 
+  last_sent_packet_id_ = options.packet_id;
   int sent = best_connection_->Send(data, len, options);
   if (sent <= 0) {
     ASSERT(sent < 0);
     error_ = best_connection_->GetError();
   }
   return sent;
 }
 
 bool P2PTransportChannel::GetStats(ConnectionInfos *infos) {
   ASSERT(worker_thread_ == rtc::Thread::Current());
@@ skipping 173 matching lines @@
     // send; then it will only signal ready-to-send if the media channel
     // has been disallowed to send.
     if (best_connection_->writable()) {
       SignalReadyToSend(this);
     }
   } else {
     LOG_J(LS_INFO, this) << "No best connection";
   }
   // TODO(honghaiz): rename best_connection_ with selected_connection_ or
   // selected_candidate pair_.
-  SignalSelectedCandidatePairChanged(this, best_connection_);
+  SignalSelectedCandidatePairChanged(this, best_connection_,
+                                     last_sent_packet_id_);
 }
 
 // Warning: UpdateState should eventually be called whenever a connection
 // is added, deleted, or the write state of any connection changes so that the
 // transport controller will get the up-to-date channel state. However it
 // should not be called too often; in the case that multiple connection states
 // change, it should be called after all the connection states have changed. For
 // example, we call this at the end of SortConnections.
 void P2PTransportChannel::UpdateState() {
   state_ = ComputeState();
@@ skipping 441 matching lines @@
 
   // During the initial state when nothing has been pinged yet, return the first
   // one in the ordered |connections_|.
   return *(std::find_if(connections_.begin(), connections_.end(),
                         [conn1, conn2](Connection* conn) {
                           return conn == conn1 || conn == conn2;
                         }));
 }
 
 }  // namespace cricket