Pass over an omitted argument as a missing parameter instead of a
numeric zero, so that optional parameters, their default values and the
basic function IsMissing() behave accordingly.
Change-Id: I7c4a65dfb1791f8aa900cc9eddd3007422dc41a0
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/209457
Tested-by: Jenkins
Reviewed-by: Andreas Heinisch <andreas.heinisch@yahoo.de>