message: tools: fix a variable name in check_format.py.
diff: @@ -817,7 +817,7 @@ def checkFormatVisitor(arg, dir_name, names):
  # python lists are passed as references, this is used to collect the list of
  # async results (futures) from running checkFormat and passing them back to
  # the caller.
  - pool, result_list, owned_directories, error_messags = arg
  + pool, result_list, owned_directories, error_messages = arg
  # Sanity check CODEOWNERS. This doesn't need to be done in a multi-threaded
  # manner as it is a small and limited list.
  