anchored to cell but changes position after reopening

Also included tdf#68797 "FILEOPEN lost position of lines
anchored to cell". It was marked as duplicate but the
step to reproduce are different.

Conflicts:
	sc/qa/unit/subsequent_filters-test.cxx

Conflicts:
	sc/qa/unit/subsequent_export-test.cxx

Reviewed-on: https://gerrit.libreoffice.org/15523Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Andras Timar <andras.timar@collabora.com>
(cherry picked from commit 487880b6)

Conflicts:
	sc/qa/unit/subsequent_export-test.cxx

Change-Id: Ia1c4010f118749256077a0ecad6ca16b867d22f7