Fix PersistentHeapHashMap to work with stack allocated, heap backed weak collections

Source/heap/Visitor.h

Index: Source/heap/Visitor.h
diff --git a/Source/heap/Visitor.h b/Source/heap/Visitor.h
index 84b7bb70f46836f5ac1722845c155eece0271003..707147fb8c64fa0763e3373d251623ba8416f8c9 100644
--- a/Source/heap/Visitor.h
+++ b/Source/heap/Visitor.h
@@ -339,7 +339,8 @@ public:
     // pointed to belong to the same thread as the object receiving
     // the weak callback. Since other threads have been resumed the
     // mark bits are not valid for objects from other threads.
-    virtual void registerWeakMembers(const void*, WeakPointerCallback) = 0;
+    virtual void registerWeakMembers(const void* object, WeakPointerCallback callback) { registerWeakMembers(object, object, callback); }
+    virtual void registerWeakMembers(const void*, const void*, WeakPointerCallback) = 0;
 
     template<typename T, void (T::*method)(Visitor*)>
     void registerWeakMembers(const T* obj)