Make length property return useful values for DOM bindings functions

Source/bindings/v8/V8DOMConfiguration.cpp

 /*
  * Copyright (C) 2012 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:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 36 matching lines @@
         prototype->Set(v8::String::NewSymbol(constant->name), v8Integer(constant->value, isolate), v8::ReadOnly);
     }
 }
 
 void V8DOMConfiguration::batchConfigureCallbacks(v8::Handle<v8::ObjectTemplate> prototype, v8::Handle<v8::Signature> signature, v8::PropertyAttribute attributes, const BatchedMethod* callbacks, size_t callbackCount, v8::Isolate*, WrapperWorldType currentWorldType)
 {
     for (size_t i = 0; i < callbackCount; ++i) {
         v8::InvocationCallback callback = callbacks[i].callback;
         if (currentWorldType == MainWorld && callbacks[i].callbackForMainWorld)
             callback = callbacks[i].callbackForMainWorld;
-        prototype->Set(v8::String::NewSymbol(callbacks[i].name), v8::FunctionTemplate::New(callback, v8Undefined(), signature), attributes);
+        prototype->Set(v8::String::NewSymbol(callbacks[i].name), v8::FunctionTemplate::New(callback, v8Undefined(), signature, callbacks[i].length), attributes);
     }
 }
 
 v8::Local<v8::Signature> V8DOMConfiguration::configureTemplate(v8::Persistent<v8::FunctionTemplate> functionDescriptor, const char* interfaceName, v8::Persistent<v8::FunctionTemplate> parentClass,
     size_t fieldCount, const BatchedAttribute* attributes, size_t attributeCount, const BatchedMethod* callbacks, size_t callbackCount, v8::Isolate* isolate, WrapperWorldType currentWorldType)
 {
     functionDescriptor->SetClassName(v8::String::NewSymbol(interfaceName));
     v8::Local<v8::ObjectTemplate> instance = functionDescriptor->InstanceTemplate();
     instance->SetInternalFieldCount(fieldCount);
     if (!parentClass.IsEmpty()) {
         functionDescriptor->Inherit(parentClass);
         // Marks the prototype object as one of native-backed objects.
         // This is needed since bug 110436 asks WebKit to tell native-initiated prototypes from pure-JS ones.
         // This doesn't mark kinds "root" classes like Node, where setting this changes prototype chain structure.
         v8::Local<v8::ObjectTemplate> prototype = functionDescriptor->PrototypeTemplate();
         prototype->SetInternalFieldCount(v8PrototypeInternalFieldcount);
     }
 
     if (attributeCount)
         batchConfigureAttributes(instance, functionDescriptor->PrototypeTemplate(), attributes, attributeCount, isolate, currentWorldType);
     v8::Local<v8::Signature> defaultSignature = v8::Signature::New(functionDescriptor);
     if (callbackCount)
         batchConfigureCallbacks(functionDescriptor->PrototypeTemplate(), defaultSignature, static_cast<v8::PropertyAttribute>(v8::DontDelete), callbacks, callbackCount, isolate, currentWorldType);
     return defaultSignature;
 }
 
 } // namespace WebCore