Oilpan: Remove GC_INFO_{DEFINE,DECLARE} macros

Source/heap/Heap.h

 /*
  * 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 842 matching lines @@
 // destructor is called on an instance when the garbage collector
 // determines that it is no longer reachable.
 template<typename T>
 class GarbageCollected {
     WTF_MAKE_NONCOPYABLE(GarbageCollected);
 
     // For now direct allocation of arrays on the heap is not allowed.
     void* operator new[](size_t size);
     void operator delete[](void* p);
 public:
+    typedef T GarbageCollectedBase;
+
     void* operator new(size_t size)
     {
         return Heap::allocate<T>(size);
     }
 
     void operator delete(void* p)
     {
         ASSERT_NOT_REACHED();
     }
 
@@ skipping 795 matching lines @@
 // to export. This forces it to export all the methods from ThreadHeap.
 template<> void ThreadHeap<FinalizedHeapObjectHeader>::addPageToHeap(const GCInfo*);
 template<> void ThreadHeap<HeapObjectHeader>::addPageToHeap(const GCInfo*);
 extern template class HEAP_EXPORT ThreadHeap<FinalizedHeapObjectHeader>;
 extern template class HEAP_EXPORT ThreadHeap<HeapObjectHeader>;
 #endif
 
 }
 
 #endif // Heap_h