bug#24714: delete-directory race condition

[Eli Zaretskii]

> Cc: eggert@cs.ucla.edu, 24714@debbugs.gnu.org
> From: Daniel Colascione <dancol@dancol.org>
> Date: Fri, 21 Oct 2016 04:53:40 -0700
> 
> > Paul, what about this Glenn's question?  The error strings are
> > localized, I think.
> 
> What about attaching the numeric errno value to the error message as a 
> text property in report_file_errno?

IMO, Glenn suggested a cleaner solution: to have a symbol for ENOENT.