Make it extra safe when deleting a turn entry.

webrtc/p2p/base/turnport.h

 /*
  *  Copyright 2012 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 201 matching lines @@
   bool ScheduleRefresh(int lifetime);
   void SendRequest(StunRequest* request, int delay);
   int Send(const void* data, size_t size,
            const rtc::PacketOptions& options);
   void UpdateHash();
   bool UpdateNonce(StunMessage* response);
 
   bool HasPermission(const rtc::IPAddress& ipaddr) const;
   TurnEntry* FindEntry(const rtc::SocketAddress& address) const;
   TurnEntry* FindEntry(int channel_id) const;
+  bool EntryExists(TurnEntry* e);
   void CreateOrRefreshEntry(const rtc::SocketAddress& address);
   void DestroyEntry(TurnEntry* entry);
   // Destroys the entry only if |timestamp| matches the destruction timestamp
   // in |entry|.
   void DestroyEntryIfNotCancelled(TurnEntry* entry, uint32_t timestamp);
   void ScheduleEntryDestruction(TurnEntry* entry);
   void CancelEntryDestruction(TurnEntry* entry);
   void OnConnectionDestroyed(Connection* conn);
 
   ProtocolAddress server_address_;
@@ skipping 26 matching lines @@
   friend class TurnEntry;
   friend class TurnAllocateRequest;
   friend class TurnRefreshRequest;
   friend class TurnCreatePermissionRequest;
   friend class TurnChannelBindRequest;
 };
 
 }  // namespace cricket
 
 #endif  // WEBRTC_P2P_BASE_TURNPORT_H_