The existing unit test (previously non-functional because of defunct
success condition) is fixed and extended.

Change-Id: I2544f865144b25f51a5f0941e5d961f246f41c4b
Reviewed-on: https://gerrit.libreoffice.org/56610
Tested-by: Jenkins
Reviewed-by: Mike Kaganski <mike.kaganski@collabora.com>