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

Source/bindings/tests/results/core/V8TestInterfaceEventInit.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 "V8TestInterfaceEventInit.h"
 
 #include "bindings/core/v8/ExceptionState.h"
@@ skipping 17 matching lines @@
     v8::Local<v8::Object> v8Object = v8Value->ToObject(isolate);
     v8::TryCatch block;
     v8::Local<v8::Value> stringMemberValue = v8Object->Get(v8String(isolate, "stringMember"));
     if (block.HasCaught()) {
         exceptionState.rethrowV8Exception(block.Exception());
         return;
     }
     if (stringMemberValue.IsEmpty() || stringMemberValue->IsUndefined()) {
         // Do nothing.
     } else {
-        TOSTRING_VOID(V8StringResource<>, stringMember, stringMemberValue);
+        V8StringResource<> stringMember = stringMemberValue;
+        if (!stringMember.prepare(exceptionState))
+            return;
         impl.setStringMember(stringMember);
     }
 
 }
 
 v8::Local<v8::Value> toV8(const TestInterfaceEventInit& impl, v8::Local<v8::Object> creationContext, v8::Isolate* isolate)
 {
     v8::Local<v8::Object> v8Object = v8::Object::New(isolate);
     toV8EventInitDictionary(impl, v8Object, creationContext, isolate);
     toV8TestInterfaceEventInit(impl, v8Object, creationContext, isolate);
     return v8Object;
 }
 
 void toV8TestInterfaceEventInit(const TestInterfaceEventInit& impl, v8::Local<v8::Object> dictionary, v8::Local<v8::Object> creationContext, v8::Isolate* isolate)
 {
     if (impl.hasStringMember()) {
         dictionary->Set(v8String(isolate, "stringMember"), v8String(isolate, impl.stringMember()));
     }
 
 }
 
 TestInterfaceEventInit NativeValueTraits<TestInterfaceEventInit>::nativeValue(const v8::Local<v8::Value>& value, v8::Isolate* isolate, ExceptionState& exceptionState)
 {
     TestInterfaceEventInit impl;
     V8TestInterfaceEventInit::toImpl(isolate, value, impl, exceptionState);
     return impl;
 }
 
 } // namespace blink