libweston-desktop/xdg_shell_v6: Raise errors on not-yet-possible requests

These requests need a mapped surface, which can only happen after the
initial configure event.

Signed-off-by: Quentin Glidic <sardemff7+git@sardemff7.net>
Reviewed-by: Jonas Ã…dahl <jadahl@gmail.com>
1 file changed