IDL: Remove holder lookup in attribute_getter macro

Source/bindings/tests/results/V8TestObject.cpp

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // This file has been auto-generated by code_generator_v8.py. DO NOT MODIFY!
 
 #include "config.h"
 #include "V8TestObject.h"
 
 #include "bindings/core/v8/V8HTMLCollection.h"
@@ skipping 4561 matching lines @@
 static void urlStringAttributeAttributeSetterCallback(v8::Local<v8::String>, v8::Local<v8::Value> v8Value, const v8::PropertyCallbackInfo<void>& info)
 {
     TRACE_EVENT_SET_SAMPLING_STATE("blink", "DOMSetter");
     CustomElementCallbackDispatcher::CallbackDeliveryScope deliveryScope;
     TestObjectV8Internal::urlStringAttributeAttributeSetter(v8Value, info);
     TRACE_EVENT_SET_SAMPLING_STATE("v8", "V8Execution");
 }
 
 static void unforgeableLongAttributeAttributeGetter(const v8::PropertyCallbackInfo<v8::Value>& info)
 {
-    v8::Handle<v8::Object> holder = V8TestObject::findInstanceInPrototypeChain(info.This(), info.GetIsolate());
-    if (holder.IsEmpty())
-        return;
+    v8::Handle<v8::Object> holder = info.Holder();
     TestObject* impl = V8TestObject::toNative(holder);
     v8SetReturnValueInt(info, impl->unforgeableLongAttribute());
 }
 
 static void unforgeableLongAttributeAttributeGetterCallback(v8::Local<v8::String>, const v8::PropertyCallbackInfo<v8::Value>& info)
 {
     TRACE_EVENT_SET_SAMPLING_STATE("blink", "DOMGetter");
     TestObjectV8Internal::unforgeableLongAttributeAttributeGetter(info);
     TRACE_EVENT_SET_SAMPLING_STATE("v8", "V8Execution");
 }
@@ skipping 5669 matching lines @@
     fromInternalPointer(object)->deref();
 }
 
 template<>
 v8::Handle<v8::Value> toV8NoInline(TestObject* impl, v8::Handle<v8::Object> creationContext, v8::Isolate* isolate)
 {
     return toV8(impl, creationContext, isolate);
 }
 
 } // namespace WebCore