...after 453fde35 "BitmapFilter::execute can be
const".  This reverts the call-site changes of
bce47223 "clang-tidy bugprone-use-after-move in
BitmapFilter::Filter" again.

Change-Id: I5ce4eb7ddce90fb779ddfb1c5864fd4785708175
Reviewed-on: https://gerrit.libreoffice.org/60255
Tested-by: Jenkins
Reviewed-by: Stephan Bergmann <sbergman@redhat.com>