For a style that isn't inserted yet, the m_sParentStyleName is converted
to UIName by setParentStyle() but isn't converted back to ProgName in
getParentStyle().
This caused all of the writerfilter test failures in commit
c166d112381f195a171425d1f9c1d38ce579319a.
Change-Id: Ib5495785996807a8f3d9339ed2740f286b04d716
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/177998
Tested-by: Jenkins
Reviewed-by: Michael Stahl <michael.stahl@allotropia.de>
