So that it's harder to introduce tabs in those files.

Change-Id: Iccaf0095fd103c4a3da44afc38f1a9d23be9863f
Reviewed-on: https://gerrit.libreoffice.org/24673Reviewed-by: Miklos Vajna <vmiklos@collabora.co.uk>
Tested-by: Jenkins <ci@libreoffice.org>