Oilpan: Remove most WillBe types from the code base

third_party/WebKit/Source/core/dom/MessageChannel.cpp

 /*
  * Copyright (C) 2008 Apple Inc. All Rights Reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 14 matching lines @@
  */
 
 #include "core/dom/MessageChannel.h"
 
 #include "core/dom/MessagePort.h"
 #include "public/platform/Platform.h"
 #include "public/platform/WebMessagePortChannel.h"
 
 namespace blink {
 
-DEFINE_EMPTY_DESTRUCTOR_WILL_BE_REMOVED(MessageChannel);
-
 static void createChannel(MessagePort* port1, MessagePort* port2)
 {
     WebMessagePortChannel* channel1;
     WebMessagePortChannel* channel2;
     Platform::current()->createMessageChannel(&channel1, &channel2);
     ASSERT(channel1 && channel2);
 
     // Now entangle the proxies with the appropriate local ports.
     port1->entangle(adoptPtr(channel2));
     port2->entangle(adoptPtr(channel1));
 }
 
 MessageChannel::MessageChannel(ExecutionContext* context)
     : m_port1(MessagePort::create(*context))
     , m_port2(MessagePort::create(*context))
 {
     createChannel(m_port1.get(), m_port2.get());
 }
 
 DEFINE_TRACE(MessageChannel)
 {
     visitor->trace(m_port1);
     visitor->trace(m_port2);
 }
 
 } // namespace blink