Use pump to generate source files.

native_mate/constructor.h

@@ -1,3 +1,7 @@
+// This file was GENERATED by command:
+//     pump.py constructor.h.pump
+// DO NOT EDIT BY HAND!!!
+
 // 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.chromium file.
@@ -30,7 +34,7 @@ inline Wrappable* InvokeFactory(
     Arguments* args,
     const base::Callback<Wrappable*(P1)>& callback) {
   typename CallbackParamTraits<P1>::LocalType a1;
-  if (!GetNextArgument(args, 0, false, &a1))
+  if (!GetNextArgument(args, 0, true, &a1))
     return NULL;
   return callback.Run(a1);
 };