bug#7784: executable-find does not find scripts on woe32

[Jason Rumney]

Eli Zaretskii <eliz@gnu.org> writes:

>> From: Óscar Fuentes <ofv@wanadoo.es>
>> Cc: Sam Steingold <sds@gnu.org>, 7784@debbugs.gnu.org
>> Date: Wed, 05 Jan 2011 15:24:26 +0100
>> 
>> One thing I noticed while experimenting with file-executable-p is that
>> it returns false for files with extensions listed in PATHEXT. For
>> instance, .JS is listed on one machine's PATHEXT but, after creating
>> foo.js, (file-executable-p "foo.js") returns nil.
>> 
>> As those files are directly executable from the shell, maybe Emacs
>> should recognize them as executables as well?
>
> Patches for supporting PATHEXT are most welcome, TIA.

It might also be a good idea to merge the list used by is_exec in w32.c
with the list that is used as the initial value of exec-suffixes.