Avoid leaking objects between isolated worlds via attribute event listeners

Source/bindings/v8/V8Binding.h

 /*
 * Copyright (C) 2009 Google Inc. All rights reserved.
 * Copyright (C) 2012 Ericsson AB. 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.
@@ skipping 322 matching lines @@
     }
 
     inline float toFloat(v8::Local<v8::Value> value)
     {
         return static_cast<float>(value->NumberValue());
     }
 
     WrapperWorldType worldType(v8::Isolate*);
     WrapperWorldType worldTypeInMainThread(v8::Isolate*);
 
+    DOMWrapperWorld* worldForIsolate(v8::Isolate*);
+
     template<class T> struct NativeValueTraits;
 
     template<>
     struct NativeValueTraits<String> {
         static inline String nativeValue(const v8::Handle<v8::Value>& value)
         {
             return toWebCoreString(value);
         }
     };
 
@@ skipping 187 matching lines @@
     template <class T>
     v8::Handle<T> unsafeHandleFromRawValue(const T* value)
     {
         const v8::Handle<T>* handle = reinterpret_cast<const v8::Handle<T>*>(&value);
         return *handle;
     }
 
 } // namespace WebCore
 
 #endif // V8Binding_h