Also revert "tdf#96257: Silly work-around to produce same result ..."
    from commit ec8bc265.

XOR rendering (it turns out) behaves oddly, and not for all operations.

Change-Id: Ie07d988bbf7fed10fb5625ac547a01a306b05319
Reviewed-on: https://gerrit.libreoffice.org/21282Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Michael Meeks <michael.meeks@collabora.com>