Fix a guard style inconsistency in regexp-stack.h.

src/regexp-stack.h

 // Copyright 2009 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 85 matching lines @@
   // Resets the buffer if it has grown beyond the default/minimum size.
   // After this, the buffer is either the default size, or it is empty, so
   // you have to call EnsureCapacity before using it again.
   static void Reset();
 
   static ThreadLocal thread_local_;
 };
 
 }}  // namespace v8::internal
 
-#endif // V8_REGEXP_STACK_H_
+#endif  // V8_REGEXP_STACK_H_