We allow the user to choose from all XKB layouts installed and keep a user picked list in gsettings. https://bugzilla.gnome.org/show_bug.cgi?id=662489
This is just the scaffolding according to https://live.gnome.org/Design/SystemSettings/RegionAndLanguage No code behind it yet. Original code from Matthias Clasen. https://bugzilla.gnome.org/show_bug.cgi?id=662489