bug#21804: 25.0.50; file-notify-tests failure on Cygwin

[Eli Zaretskii]

> From: Ken Brown <kbrown@cornell.edu>
> Date: Thu, 29 Dec 2016 15:33:15 -0500
> Cc: 21804@debbugs.gnu.org
> 
> -         (string-equal (file-notify--test-monitor) "GPollFileMonitor"))
> +          (or (string-equal (file-notify--test-monitor) "GPollFileMonitor")
> +              (string-equal (file-notify--test-monitor) "GFamFileMonitor")))

Wouldn't it be better if gfile-monitor-name returned a symbol instead
of a string?  That's our general convention with functions, I think.