GDBusMenuModel: Allow NULL bus name for peer-to-peer connection
GDBusMenuModel: Allow NULL bus name for peer-to-peer connection

https://bugzilla.gnome.org/show_bug.cgi?id=720380

endlessm/glib,johne53/MB3Glib,johne53/MB3Glib,johne53/MB3Glib,endlessm/glib,endlessm/glib,endlessm/glib,johne53/MB3Glib,endlessm/glib,johne53/MB3Glib,johne53/MB3Glib