Oilpan: tidy up prefinalizer declarations and a registration.

Source/platform/LifecycleObserver.h

 /*
  * 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 16 matching lines @@
 #ifndef LifecycleObserver_h
 #define LifecycleObserver_h
 
 #include "platform/heap/Handle.h"
 #include "wtf/Assertions.h"
 
 namespace blink {
 
 template<typename T>
 class LifecycleObserver : public WillBeGarbageCollectedMixin {
-    // FIXME: Oilpan: Remove the pre-finalizer by moving LifecycleNotifer
-    // to Oilpan's heap and making LifecycleNotifer::m_observers
+    // FIXME: Oilpan: Remove the pre-finalizer by moving LifecycleNotifier
+    // to Oilpan's heap and making LifecycleNotifier::m_observers
     // a hash set of weak members.
-#if ENABLE(OILPAN)
-    USING_PRE_FINALIZER(LifecycleObserver, dispose);
-#endif
+    WILL_BE_USING_PRE_FINALIZER(LifecycleObserver, dispose);
 public:
     typedef T Context;
 
     enum Type {
         ActiveDOMObjectType,
         DocumentLifecycleObserverType,
         GenericType,
         PageLifecycleObserverType,
         DOMWindowLifecycleObserverType
     };
@@ skipping 50 matching lines @@
 
     m_lifecycleContext = context;
 
     if (m_lifecycleContext)
         observerContext(m_lifecycleContext.get(), this);
 }
 
 } // namespace blink
 
 #endif // LifecycleObserver_h