to match the type used by X11

Change-Id: I5fe043e33602be21c84b81780c89df751c3bc96c
Reviewed-on: https://gerrit.libreoffice.org/46393Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>
Tested-by: Noel Grandin <noel.grandin@collabora.co.uk>