xdg-shell/toplevel: Clarify xdg_toplevel.set_parent(null)

Setting a null-surface as a toplevel parent should unset the
parent-child relationship. This was not specified, so lets do that.

Signed-off-by: Jonas Ådahl <jadahl@gmail.com>
Signed-off-by: Mike Blumenkrantz <zmike@osg.samsung.com>
1 file changed