fdo#79731 fdo#85813 drawingML export: fix handling of impress tables

(cherry picked from commit 02e52b15908a6d89b4aeb3c349e7414240eb9563)
Signed-off-by: Andras Timar <andras.timar@collabora.com>

Conflicts:
	oox/source/export/drawingml.cxx
	sd/qa/unit/export-tests.cxx

Change-Id: Ia17b14c4b27e808ceab388aa33602875e67433a5