more accurate typing

Change-Id: Ibccf8c5cf520b79da0914eccbebdbb68601dd0f1
Reviewed-on: https://gerrit.libreoffice.org/11314
Reviewed-by: Lionel Elie Mamane <lionel@mamane.lu>
Tested-by: Lionel Elie Mamane <lionel@mamane.lu>
Reviewed-by: Norbert Thiebaud <nthiebaud@gmail.com>
Tested-by: Norbert Thiebaud <nthiebaud@gmail.com>