Simplify the magic required to create IPC message headers a bit.

ipc/ipc_sync_message_unittest.cc

 // Copyright (c) 2006-2008 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.
 //
 // Unit test to make sure that the serialization of synchronous IPC messages
 // works.  This ensures that the macros and templates were defined correctly.
 // Doesn't test the IPC channel mechanism.
 
 #include <string.h>
 
 #include "base/basictypes.h"
 #include "ipc/ipc_message.h"
 #include "ipc/ipc_message_utils.h"
 #include "base/logging.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
-
-#define MESSAGES_INTERNAL_FILE "ipc/ipc_sync_message_unittest.h"
-#include "ipc/ipc_message_macros.h"
+#define IPC_MESSAGE_IMPL
+#include "ipc/ipc_sync_message_unittest.h"
 
 static IPC::Message* g_reply;
 
 class TestMessageReceiver {
  public:
 
   void On_0_1(bool* out1) {
     *out1 = false;
   }
 
@@ skipping 226 matching lines @@
   DCHECK(bool1);
 
   bool1 = false;
   Send(new Msg_R_3_2(0, "3_2", false, 2, &bool1, &int1));
   DCHECK(bool1 && int1 == 32);
 
   bool1 = true;
   Send(new Msg_R_3_3(0, 3, "3_3", true, &string1, &int1, &bool1));
   DCHECK(string1 == "3_3" && int1 == 33 && !bool1);
 }