and use references instead of pointers for output parameters.

Change-Id: Ib91a821ff84e464639aa6f09a44ba00301f1d783
Reviewed-on: https://gerrit.libreoffice.org/39220Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>