Inherit EventTarget interface instead of duplicating its code

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 43 matching lines @@
 
     RefPtr<SecurityOrigin> securityOrigin;
     if (context->isDocument()) {
         if (DOMWrapperWorld* world = isolatedWorldForEnteredContext())
             securityOrigin = world->isolatedWorldSecurityOrigin();
     }
 
     RefPtr<XMLHttpRequest> xmlHttpRequest = XMLHttpRequest::create(context, securityOrigin);
 
     v8::Handle<v8::Object> wrapper = args.Holder();
-    V8DOMWrapper::associateObjectWithWrapper(xmlHttpRequest.release(), &info, wrapper, args.GetIsolate(), WrapperConfiguration::Dependent);
+    V8DOMWrapper::associateObjectWithWrapper<V8XMLHttpRequest>(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;
     ScriptValue text = xmlHttpRequest->responseText(ec);
     if (ec) {
         setDOMException(ec, info.GetIsolate());
@@ skipping 151 matching lines @@
             xmlHttpRequest->send(toWebCoreStringWithNullCheck(arg), ec);
     }
 
     if (!ec)
         return;
 
     setDOMException(ec, args.GetIsolate());
 }
 
 } // namespace WebCore