Small simplification of #include dependencies.

src/debug.cc

 // Copyright 2006-2008 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 21 matching lines @@
 #include "bootstrapper.h"
 #include "code-stubs.h"
 #include "codegen.h"
 #include "compilation-cache.h"
 #include "compiler.h"
 #include "debug.h"
 #include "execution.h"
 #include "global-handles.h"
 #include "ic.h"
 #include "ic-inl.h"
+#include "messages.h"
 #include "natives.h"
 #include "stub-cache.h"
 #include "log.h"
 
 #include "../include/v8-debug.h"
 
 namespace v8 {
 namespace internal {
 
 #ifdef ENABLE_DEBUGGER_SUPPORT
@@ skipping 2747 matching lines @@
     {
       Locker locker;
       Debugger::CallMessageDispatchHandler();
     }
   }
 }
 
 #endif  // ENABLE_DEBUGGER_SUPPORT
 
 } }  // namespace v8::internal