Use new phantom handles for ScriptWrappable.

Source/bindings/core/v8/V8PersistentValueMap.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 30 matching lines @@
  * A Traits class for v8::PersistentValueMap that uses wtf/HashMap as a
  * backing store.
  *
  * The parameter is_weak will determine whether the references are 'weak'.
  * If so, entries will be removed from the map as the weak references are
  * collected.
  */
 template<class KeyType, class ValueType, bool is_weak>
 class V8PersistentValueMapTraits {
 public:
+    static const bool kUseSetWeak = true;
     // Map traits:
     typedef HashMap<KeyType, v8::PersistentContainerValue> Impl;
     typedef typename Impl::iterator Iterator;
     static size_t Size(const Impl* impl) { return impl->size(); }
     static bool Empty(Impl* impl) { return impl->isEmpty(); }
     static void Swap(Impl& impl, Impl& other) { impl.swap(other); }
     static Iterator Begin(Impl* impl) { return impl->begin(); }
     static Iterator End(Impl* impl) { return impl->end(); }
     static v8::PersistentContainerValue Value(Iterator& iter)
     {
@@ skipping 58 matching lines @@
 template<class KeyType, class ValueType, bool is_weak = true>
 class V8PersistentValueMap : public v8::PersistentValueMap<KeyType, ValueType, V8PersistentValueMapTraits<KeyType, ValueType, is_weak> > {
 public:
     typedef V8PersistentValueMapTraits<KeyType, ValueType, is_weak> Traits;
     explicit V8PersistentValueMap(v8::Isolate* isolate) : v8::PersistentValueMap<KeyType, ValueType, Traits>(isolate) { }
 };
 
 } // namespace blink
 
 #endif // V8PersistentValueMap_h