Oilpan: make DOMWindowProperty a GC mixin.

Source/modules/quota/NavigatorStorageQuota.cpp

 /*
  * Copyright (C) 2013 Google 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 24 matching lines @@
 #include "modules/quota/DeprecatedStorageQuota.h"
 #include "modules/quota/StorageQuota.h"
 
 namespace blink {
 
 NavigatorStorageQuota::NavigatorStorageQuota(LocalFrame* frame)
     : DOMWindowProperty(frame)
 {
 }
 
-NavigatorStorageQuota::~NavigatorStorageQuota()
-{
-}
+DEFINE_EMPTY_DESTRUCTOR_WILL_BE_REMOVED(NavigatorStorageQuota);
 
 const char* NavigatorStorageQuota::supplementName()
 {
     return "NavigatorStorageQuota";
 }
 
 NavigatorStorageQuota& NavigatorStorageQuota::from(Navigator& navigator)
 {
     NavigatorStorageQuota* supplement = static_cast<NavigatorStorageQuota*>(WillBeHeapSupplement<Navigator>::from(navigator, supplementName()));
     if (!supplement) {
@@ skipping 38 matching lines @@
         m_persistentStorage = DeprecatedStorageQuota::create(DeprecatedStorageQuota::Persistent);
     return m_persistentStorage.get();
 }
 
 void NavigatorStorageQuota::trace(Visitor* visitor)
 {
     visitor->trace(m_storageQuota);
     visitor->trace(m_temporaryStorage);
     visitor->trace(m_persistentStorage);
     WillBeHeapSupplement<Navigator>::trace(visitor);
+    DOMWindowProperty::trace(visitor);
 }
 
 } // namespace blink