mac: Make Mach port scopers better ScopedGenerics

sandbox/mac/xpc_message_server.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "sandbox/mac/xpc_message_server.h"
 
 #include <bsm/libbsm.h>
 
 #include <string>
 
@@ skipping 86 matching lines @@
     SendReply(reply);
   }
 }
 
 mach_port_t XPCMessageServer::GetServerPort() const {
   return server_port_.get();
 }
 
 void XPCMessageServer::ReceiveMessage() {
   IPCMessage request;
-  int rv = xpc_pipe_receive(server_port_, &request.xpc);
+  int rv = xpc_pipe_receive(server_port_.get(), &request.xpc);
   if (rv) {
     LOG(ERROR) << "Failed to xpc_pipe_receive(): " << rv;
     return;
   }
 
   demuxer_->DemuxMessage(request);
 
   xpc_release(request.xpc);
   if (reply_message_) {
     xpc_release(reply_message_);
     reply_message_ = NULL;
   }
 }
 
 }  // namespace sandbox