Oilpan: Move LifecycleNotifier's hierarchy to Oilpan's heap

Source/platform/LifecycleContextTest.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:
  * 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 17 matching lines @@
 
 #include "platform/LifecycleNotifier.h"
 #include "platform/heap/Handle.h"
 #include <gtest/gtest.h>
 
 using namespace blink;
 
 namespace blink {
 
 class DummyContext final : public NoBaseWillBeGarbageCollectedFinalized<DummyContext>, public LifecycleNotifier<DummyContext> {
+    WILL_BE_USING_GARBAGE_COLLECTED_MIXIN(DummyContext);
 public:
     DummyContext()
         : LifecycleNotifier<DummyContext>(this)
     {
     }
 
     void trace(Visitor* visitor)
     {
         LifecycleNotifier<DummyContext>::trace(visitor);
     }
@@ skipping 53 matching lines @@
     Persistent<TestingObserver> observer = new TestingObserver(context.get());
     observer->unobserve();
     context->notifyContextDestroyed();
     context = nullptr;
     Heap::collectAllGarbage();
     EXPECT_EQ(observer->lifecycleContext(), static_cast<DummyContext*>(0));
     EXPECT_FALSE(observer->m_contextDestroyedCalled);
 }
 
 }