Fix missing return from quartz_filter_keypress

(cherry picked from commit 0ae728e2424406f1dab3878a31942d9dd8862c1a)
Fix config dir <> data dir confusion

We added code to look for gtkrc in system config dirs,
and then proceeded to move it to /usr/share/gtk-2.0 :-(.
So, look in that location as well.
Merge branch 'gtk-2-24' of git://git.gnome.org/gtk+ into gtk-2-24