bug#25895: Remove update-game-score

[Eli Zaretskii]

> Cc: ulm@gentoo.org, 25895@debbugs.gnu.org
> From: Paul Eggert <eggert@cs.ucla.edu>
> Date: Sun, 12 Mar 2017 00:45:13 -0800
> 
> Eli Zaretskii wrote:
> 
> > Please add comments to the affected Makefile.in files to explain the
> > conditions related to user/group.
> 
> Done in the attached revised patch, which also fixes the bug Ulrich Müller 
> noted.

Thanks, but I expected to see there the explanation of why we
sometimes expect user/group to be empty and sometimes not.  IOW, I'd
like to have in the affected Makefile a comment which summarized the
rationale in the commit message, something akin to this:

> Most distributions do not install update-game-score properly
> due to setuid/setgid complications, so install it only when
> the installer specifies a user or group (Bug#25895).

> > I also don't understand why you unconditionally removed this program
> > from the Windows builds and installations: the problem with setgid
> > doesn't exist on Windows, so nothing should prevent Windows
> > installations from having this program, right?
> 
> It's more the other way round. On platforms without setuid/setgid, Emacs can 
> use 
> its already-existing code to update the score file itself. The auxiliary 
> program 
> is needed only on platforms that have setuid/setgid, to avoid the security 
> problems that would ensue if we made Emacs itself setuid/setgid.

Ah, yes.  Thanks for clarifying this.