glib freeze break request

[Colin Walters <walters verbum org>]

Hi,

https://bugzilla.gnome.org/show_bug.cgi?id=696014

This is pretty critical for ostree since it makes /etc/shadow
world-readable.  It can still be a less severe security issue in some
cases such as making files in your home directory world-readable if they
weren't originally.

I've tested this patch a lot and believe it's quite low risk.