bug#25825: 25.1; ispell-find-hunspell-dictionaries not working on Windows

[Stefan Kangas <stefan@marxist.se>]

Eli Zaretskii <eliz@gnu.org> writes:

> Looks like you have an installation problem: there's no default.dic on
> your system.

It seems to be an issue with my environment.  I've been using this for a
very long time:

    $ locale
    LANG=
    LANGUAGE=
    LC_CTYPE=sv_SE.UTF-8
    LC_NUMERIC="POSIX"
    LC_TIME=C
    LC_COLLATE=C
    LC_MONETARY="POSIX"
    LC_MESSAGES="POSIX"
    LC_PAPER="POSIX"
    LC_NAME="POSIX"
    LC_ADDRESS="POSIX"
    LC_TELEPHONE="POSIX"
    LC_MEASUREMENT="POSIX"
    LC_IDENTIFICATION="POSIX"
    LC_ALL=

But for some reason, hunspell is very sensitive and will not give any
loaded dictionary if $LANG is unset.  (IMO, very unhelpful behaviour.)

This gives the expected output:

    $ export LANG=en_US.UTF-8
    $ hunspell -D /dev/null
    SEARCH PATH:
    [[...snipped...]]
    AVAILABLE DICTIONARIES (path is not mandatory for -d option):
    /usr/share/hunspell/en_US
    /usr/share/hunspell/sv_FI
    /usr/share/hunspell/sv_SE
    /home/skangas/.openoffice.org/3/user/wordbook/standard
    LOADED DICTIONARY:
    /usr/share/hunspell/en_US.aff
    /usr/share/hunspell/en_US.dic

One idea to improve the situation on our end is to look for "Can't
open affix or dictionary files for dictionary named 'default'." and
raise a better error in these cases.

Or, if we want to really go out of our way, we could retry with
"LANG=en_US.UTF-8".

WDYT?