Make DOMWrapperWorld::current() return a reference instead of a pointer

Source/bindings/v8/custom/V8XMLHttpRequestCustom.cpp

 /*
  * Copyright (C) 2008, 2009, 2010 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 39 matching lines @@
 #include <v8.h>
 
 namespace WebCore {
 
 void V8XMLHttpRequest::constructorCustom(const v8::FunctionCallbackInfo<v8::Value>& info)
 {
     ExecutionContext* context = currentExecutionContext(info.GetIsolate());
 
     RefPtr<SecurityOrigin> securityOrigin;
     if (context->isDocument()) {
-        DOMWrapperWorld* world = DOMWrapperWorld::current(info.GetIsolate());
-        if (world->isIsolatedWorld())
-            securityOrigin = world->isolatedWorldSecurityOrigin();
+        DOMWrapperWorld& world = DOMWrapperWorld::current(info.GetIsolate());
+        if (world.isIsolatedWorld())
+            securityOrigin = world.isolatedWorldSecurityOrigin();
     }
 
     RefPtrWillBeRawPtr<XMLHttpRequest> xmlHttpRequest = XMLHttpRequest::create(context, securityOrigin);
 
     v8::Handle<v8::Object> wrapper = info.Holder();
     V8DOMWrapper::associateObjectWithWrapper<V8XMLHttpRequest>(xmlHttpRequest.release(), &wrapperTypeInfo, wrapper, info.GetIsolate(), WrapperConfiguration::Dependent);
     info.GetReturnValue().Set(wrapper);
 }
 
 void V8XMLHttpRequest::responseTextAttributeGetterCustom(const v8::PropertyCallbackInfo<v8::Value>& info)
@@ skipping 172 matching lines @@
         } else {
             V8TRYCATCH_FOR_V8STRINGRESOURCE_VOID(V8StringResource<WithNullCheck>, argString, arg);
             xmlHttpRequest->send(argString, exceptionState);
         }
     }
 
     exceptionState.throwIfNeeded();
 }
 
 } // namespace WebCore