bug#25340: Save-some-buffers gets called when installing packages.

[Andreas Politz]

npostavs@users.sourceforge.net writes:

> I was thinking more along the lines of
>
>     (string-prefix-p (expand-file-name directory)
>                      (expand-file-name buffer-file-name))
>

Why not use `file-in-directory-p', which is a function created for this
problem.

-ap