Partially revert 56039daae4a436d7ea1b093a02cf0e8ad3bda4a9
"tdf#149673: only check opacity from parent..." to make
getOpacity behave as before and move the new behaviour
of getOpacity inside add_postProcess
Change-Id: If475cddbc4967308fa06adacda621cb3790c6f70
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/170376
Reviewed-by: Xisco Fauli <xiscofauli@libreoffice.org>
Tested-by: Jenkins
8c5f93ee35
