Add MakeUnique from chromium and change StunMessage::AddAttribute to take a unique_ptr.

webrtc/p2p/base/stunserver.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 44 matching lines @@
   SendResponse(response, remote_addr);
 }
 
 void StunServer::SendErrorResponse(
     const StunMessage& msg, const rtc::SocketAddress& addr,
     int error_code, const char* error_desc) {
   StunMessage err_msg;
   err_msg.SetType(GetStunErrorResponseType(msg.type()));
   err_msg.SetTransactionID(msg.transaction_id());
 
-  StunErrorCodeAttribute* err_code = StunAttribute::CreateErrorCode();
+  auto err_code = StunAttribute::CreateErrorCode();
   err_code->SetCode(error_code);
   err_code->SetReason(error_desc);
-  err_msg.AddAttribute(err_code);
+  err_msg.AddAttribute(std::move(err_code));
 
   SendResponse(err_msg, addr);
 }
 
 void StunServer::SendResponse(
     const StunMessage& msg, const rtc::SocketAddress& addr) {
   rtc::ByteBufferWriter buf;
   msg.Write(&buf);
   rtc::PacketOptions options;
   if (socket_->SendTo(buf.Data(), buf.Length(), addr, options) < 0)
     LOG_ERR(LS_ERROR) << "sendto";
 }
 
 void StunServer::GetStunBindReqponse(StunMessage* request,
                                      const rtc::SocketAddress& remote_addr,
                                      StunMessage* response) const {
   response->SetType(STUN_BINDING_RESPONSE);
   response->SetTransactionID(request->transaction_id());
 
   // Tell the user the address that we received their request from.
-  StunAddressAttribute* mapped_addr;
+  std::unique_ptr<StunAddressAttribute> mapped_addr;
   if (!request->IsLegacy()) {
     mapped_addr = StunAttribute::CreateAddress(STUN_ATTR_MAPPED_ADDRESS);
   } else {
     mapped_addr = StunAttribute::CreateXorAddress(STUN_ATTR_XOR_MAPPED_ADDRESS);
   }
   mapped_addr->SetAddress(remote_addr);
-  response->AddAttribute(mapped_addr);
+  response->AddAttribute(std::move(mapped_addr));
 }
 
 }  // namespace cricket