A few updates on connection states

webrtc/p2p/base/p2ptransportchannel.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.
  */
 
@@ skipping 144 matching lines @@
 
   // Public for unit tests.
   Connection* FindNextPingableConnection();
 
  private:
   rtc::Thread* thread() { return worker_thread_; }
   PortAllocatorSession* allocator_session() {
     return allocator_sessions_.back();
   }
 
+  // A transport channel is weak if the current best connection is either
+  // not receiving or not writable, or if there is no best connection at all.
+  bool Weak() const;
   void UpdateConnectionStates();
   void RequestSort();
   void SortConnections();
   void SwitchBestConnectionTo(Connection* conn);
   void UpdateChannelState();
   void HandleWritable();
   void HandleNotWritable();
   void HandleAllTimedOut();
 
   Connection* GetBestConnectionOnNetwork(rtc::Network* network) const;
@@ skipping 29 matching lines @@
   void OnConnectionStateChange(Connection* connection);
   void OnReadPacket(Connection *connection, const char *data, size_t len,
                     const rtc::PacketTime& packet_time);
   void OnReadyToSend(Connection* connection);
   void OnConnectionDestroyed(Connection *connection);
 
   void OnNominated(Connection* conn);
 
   void OnMessage(rtc::Message* pmsg) override;
   void OnSort();
-  void OnPing();
-
-  void OnCheckReceiving();
+  void OnCheckAndPing();
 
   void PruneConnections();
   Connection* best_nominated_connection() const;
 
   P2PTransport* transport_;
   PortAllocator* allocator_;
   rtc::Thread* worker_thread_;
   bool incoming_only_;
   int error_;
   std::vector<PortAllocatorSession*> allocator_sessions_;
@@ skipping 14 matching lines @@
   std::string remote_ice_ufrag_;
   std::string remote_ice_pwd_;
   IceMode remote_ice_mode_;
   IceRole ice_role_;
   uint64 tiebreaker_;
   uint32 remote_candidate_generation_;
   IceGatheringState gathering_state_;
 
   int check_receiving_delay_;
   int receiving_timeout_;
+  uint32 last_ping_sent_ms_ = 0;
 
   RTC_DISALLOW_COPY_AND_ASSIGN(P2PTransportChannel);
 };
 
 }  // namespace cricket
 
 #endif  // WEBRTC_P2P_BASE_P2PTRANSPORTCHANNEL_H_