Inherit EventTarget interface instead of duplicating its code

Source/bindings/v8/custom/V8FormDataCustom.cpp

 /*
  * Copyright (C) 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 29 matching lines @@
 namespace WebCore {
 
 void V8FormData::constructorCustom(const v8::FunctionCallbackInfo<v8::Value>& args)
 {
     HTMLFormElement* form = 0;
     if (args.Length() > 0 && V8HTMLFormElement::HasInstance(args[0], args.GetIsolate(), worldType(args.GetIsolate())))
         form = V8HTMLFormElement::toNative(args[0]->ToObject());
     RefPtr<DOMFormData> domFormData = DOMFormData::create(form);
 
     v8::Handle<v8::Object> wrapper = args.Holder();
-    V8DOMWrapper::associateObjectWithWrapper(domFormData.release(), &info, wrapper, args.GetIsolate(), WrapperConfiguration::Dependent);
+    V8DOMWrapper::associateObjectWithWrapper<V8FormData>(domFormData.release(), &info, wrapper, args.GetIsolate(), WrapperConfiguration::Dependent);
     args.GetReturnValue().Set(wrapper);
 }
 
 void V8FormData::appendMethodCustom(const v8::FunctionCallbackInfo<v8::Value>& args)
 {
     if (args.Length() < 2) {
         throwError(v8SyntaxError, "Not enough arguments", args.GetIsolate());
         return;
     }
 
@@ skipping 10 matching lines @@
         String filename;
         if (args.Length() >= 3 && !args[2]->IsUndefined())
             filename = toWebCoreStringWithNullCheck(args[2]);
 
         domFormData->append(name, blob, filename);
     } else
         domFormData->append(name, toWebCoreStringWithNullCheck(arg));
 }
 
 } // namespace WebCore