Oilpan: Fix a wrong comment on a Persistent handle

Source/platform/heap/Handle.h

 /*
  * Copyright (C) 2014 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 251 matching lines @@
     inline void recordBacktrace() const { }
 #endif
     // m_raw is accessed most, so put it at the first field.
     T* m_raw;
     PersistentNode* m_persistentNode;
 #if ENABLE(ASSERT)
     ThreadState* m_state;
 #endif
 };
 
-// Persistent is a way to create a strong pointer from an on-heap object
+// Persistent is a way to create a strong pointer from an off-heap object
 // to another on-heap object. As long as the Persistent handle is alive
 // the GC will keep the object pointed to alive. The Persistent handle is
 // always a GC root from the point of view of the GC.
 //
 // We have to construct and destruct Persistent in the same thread.
 template<typename T>
 class Persistent : public PersistentBase<T, NonWeakPersistentConfiguration, SingleThreadPersistentConfiguration> {
     typedef PersistentBase<T, NonWeakPersistentConfiguration, SingleThreadPersistentConfiguration> Parent;
 public:
     Persistent() : Parent() { }
@@ skipping 896 matching lines @@
 struct ParamStorageTraits<RawPtr<T>> : public PointerParamStorageTraits<T*, blink::IsGarbageCollectedType<T>::value> {
     static_assert(sizeof(T), "T must be fully defined");
 };
 
 template<typename T>
 PassRefPtr<T> adoptRef(blink::RefCountedGarbageCollected<T>*) = delete;
 
 } // namespace WTF
 
 #endif