bug#20839: 25.0.50; file-in-directory-p doesn't understand windows backslashes

[Eli Zaretskii]

> Date: Wed, 17 Jun 2015 21:13:13 +0100
> From: Artur Malabarba <bruce.connor.am@gmail.com>
> Cc: 20839@debbugs.gnu.org
> 
> I was aiding someone remotely and I assumed this was the issue. I'll ask them
> to file a bug report themselves. 

I see no bug report, and I suspect the user might be contempt with the
"sledgehammer" (their word) solution mentioned there, and so that
report will never materialize.  Should we close this bug?

Meanwhile, the offending line cited there, viz.:

  ((not (file-in-directory-p dir package-user-dir)) "external")

has one more unknown, as far as I'm concerned: the value of 'dir'.
That comes from this, AFAICS:

  (package-desc-dir pkg-desc)

So it would e nice if the value that comes out of that on that user's
system could be reported.

Also, could any of the other packages that user loads overload the
functions involved in calculating file-in-directory-p?

Those are the ideas I had, anyway.