Since we don't yet have a way to export gsettings into a system wide
store g-c-c exports input sources as XKB layouts through the locald
DBus API which stores them in an xorg.conf.d file which the X server
uses to configure itself initially.

This means that, when running under GDM, we should consider the
current X server's layouts the canonical setting for input sources and
thus always use them instead of whatever we have in the GDM user's
gsetting.

https://bugzilla.gnome.org/show_bug.cgi?id=684586