When using appearing animations on shapes, some of the slide transitions
incorrectly don't show these shapes. Same for disappearing shapes - both
states are wrong during slide transition time. Fix slide bitmap
generator to take final slide states into account.

Change-Id: Iea0e576009a109c7f44a7a6498b0ee5b2c4791c5
Reviewed-on: https://gerrit.libreoffice.org/20199Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Thorsten Behrens <Thorsten.Behrens@CIB.de>