IDL compiler: move EventHandler null check out of generated bindings

Source/bindings/v8/V8Utilities.cpp

 /*
  * Copyright (C) 2008, 2009 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 131 matching lines @@
 void transferHiddenDependency(v8::Handle<v8::Object> object, EventListener* oldValue, v8::Local<v8::Value> newValue, int cacheIndex, v8::Isolate* isolate)
 {
     if (oldValue) {
         V8AbstractEventListener* oldListener = V8AbstractEventListener::cast(oldValue);
         if (oldListener) {
             v8::Local<v8::Object> oldListenerObject = oldListener->getExistingListenerObject();
             if (!oldListenerObject.IsEmpty())
                 removeHiddenDependency(object, oldListenerObject, cacheIndex, isolate);
         }
     }
+    // Non-callable input should be treated as null
+    if (!newValue->IsNull() && !newValue->IsFunction())
+        newValue = v8::Null(isolate);
     if (!newValue->IsNull() && !newValue->IsUndefined())
         createHiddenDependency(object, newValue, cacheIndex, isolate);
 }
 
 ExecutionContext* getExecutionContext()
 {
     if (WorkerScriptController* controller = WorkerScriptController::controllerForContext())
         return &controller->workerGlobalScope();
 
     return currentDocument();
 }
 
 } // namespace WebCore