cascading conditional operators, give a hint on complexity

Change-Id: Ie9d0b07a32cc17705db735ea18f70f28d57badd4
Reviewed-on: https://gerrit.libreoffice.org/12990
Reviewed-by: Björn Michaelsen <bjoern.michaelsen@canonical.com>
Tested-by: Björn Michaelsen <bjoern.michaelsen@canonical.com>