Adding logs to track potential cause of not starting port allocation.

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 292 matching lines @@
                               << " has more than 1 connection.";
       return TransportChannelState::STATE_CONNECTING;
     }
   }
 
   return TransportChannelState::STATE_COMPLETED;
 }
 
 void P2PTransportChannel::SetIceParameters(const IceParameters& ice_params) {
   ASSERT(worker_thread_ == rtc::Thread::Current());
+  LOG(LS_INFO) << "Set ICE ufrag: "<< ice_params.ufrag
+               << " pwd: " << ice_params.pwd
+               << " on transport "<< transport_name();

[Taylor Brandstetter, 2016/09/14 20:39:04]

nit: Missing whitespace, can probably do git cl format

[honghaiz3, 2016/09/15 17:38:29]

Done.

   ice_parameters_ = ice_params;
   // Note: Candidate gathering will restart when MaybeStartGathering is next
   // called.
 }
 
 void P2PTransportChannel::SetRemoteIceParameters(
     const IceParameters& ice_params) {
   ASSERT(worker_thread_ == rtc::Thread::Current());
   LOG(LS_INFO) << "Remote supports ICE renomination ? "
                << ice_params.renomination;
@@ skipping 104 matching lines @@
                  << static_cast<int>(config_.default_nomination_mode);
   }
 }
 
 const IceConfig& P2PTransportChannel::config() const {
   return config_;
 }
 
 void P2PTransportChannel::MaybeStartGathering() {
   if (ice_parameters_.ufrag.empty() || ice_parameters_.pwd.empty()) {
+    LOG(LS_ERROR) << "Cannot gather candidates because ICE parameters are empty"
+                  << " ufrag: " << ice_parameters_.ufrag
+                  << " pwd: " << ice_parameters_.pwd;
     return;
   }
   // Start gathering if we never started before, or if an ICE restart occurred.
   if (allocator_sessions_.empty() ||
       IceCredentialsChanged(allocator_sessions_.back()->ice_ufrag(),
                             allocator_sessions_.back()->ice_pwd(),
                             ice_parameters_.ufrag, ice_parameters_.pwd)) {
     if (gathering_state_ != kIceGatheringGathering) {
       gathering_state_ = kIceGatheringGathering;
       SignalGatheringState(this);
@@ skipping 1513 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