IDL: Drop value conversion (V8 -> C++) macros from generated code

Source/bindings/tests/results/core/V8TestInterfaceConstructor3.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 "V8TestInterfaceConstructor3.h"
 
 #include "bindings/core/v8/ExceptionState.h"
@@ skipping 20 matching lines @@
 namespace TestInterfaceConstructor3V8Internal {
 
 static void constructor(const v8::FunctionCallbackInfo<v8::Value>& info)
 {
     if (UNLIKELY(info.Length() < 1)) {
         V8ThrowException::throwException(createMinimumArityTypeErrorForConstructor(info.GetIsolate(), "TestInterfaceConstructor3", 1, info.Length()), info.GetIsolate());
         return;
     }
     V8StringResource<> stringArg;
     {
-        TOSTRING_VOID_INTERNAL(stringArg, info[0]);
+        TONATIVE_CONVERT((stringArg = info[0]).prepare(), return);
     }
     RefPtr<TestInterfaceConstructor3> impl = TestInterfaceConstructor3::create(stringArg);
     v8::Local<v8::Object> wrapper = info.Holder();
     impl->associateWithWrapper(info.GetIsolate(), &V8TestInterfaceConstructor3::wrapperTypeInfo, wrapper);
     v8SetReturnValue(info, wrapper);
 }
 
 } // namespace TestInterfaceConstructor3V8Internal
 
 void V8TestInterfaceConstructor3::constructorCallback(const v8::FunctionCallbackInfo<v8::Value>& info)
@@ skipping 56 matching lines @@
 {
     scriptWrappable->toImpl<TestInterfaceConstructor3>()->ref();
 }
 
 void V8TestInterfaceConstructor3::derefObject(ScriptWrappable* scriptWrappable)
 {
     scriptWrappable->toImpl<TestInterfaceConstructor3>()->deref();
 }
 
 } // namespace blink