XMLHttpRequest#responseText should use a rope

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 52 matching lines @@
 
     v8::Handle<v8::Object> wrapper = args.Holder();
     V8DOMWrapper::associateObjectWithWrapper(xmlHttpRequest.release(), &info, wrapper, args.GetIsolate(), WrapperConfiguration::Dependent);
     args.GetReturnValue().Set(wrapper);
 }
 
 void V8XMLHttpRequest::responseTextAttrGetterCustom(v8::Local<v8::String> name, const v8::PropertyCallbackInfo<v8::Value>& info)
 {
     XMLHttpRequest* xmlHttpRequest = V8XMLHttpRequest::toNative(info.Holder());
     ExceptionCode ec = 0;
-    const String& text = xmlHttpRequest->responseText(ec);
+    ScriptValue text = xmlHttpRequest->responseText(ec);
     if (ec) {
         setDOMException(ec, info.GetIsolate());
         return;
     }
-    v8SetReturnValue(info, v8String(text, info.GetIsolate()));
+    if (text.hasNoValue()) {
+        v8SetReturnValue(info, v8String(emptyString(), info.GetIsolate()));
+        return;
+    }
+    v8SetReturnValue(info, text.v8Value());
 }
 
 void V8XMLHttpRequest::responseAttrGetterCustom(v8::Local<v8::String> name, const v8::PropertyCallbackInfo<v8::Value>& info)
 {
     XMLHttpRequest* xmlHttpRequest = V8XMLHttpRequest::toNative(info.Holder());
 
     switch (xmlHttpRequest->responseTypeCode()) {
     case XMLHttpRequest::ResponseTypeDefault:
     case XMLHttpRequest::ResponseTypeText:
         responseTextAttrGetterCustom(name, info);
@@ skipping 134 matching lines @@
             xmlHttpRequest->send(toWebCoreStringWithNullCheck(arg), ec);
     }
 
     if (!ec)
         return;
 
     setDOMException(ec, args.GetIsolate());
 }
 
 } // namespace WebCore