Regression from commit 961ba62d
(tdf#123032 sw, AddVerticalFrameOffsets: fix shape pos after mouse move,
2019-02-07), the vertical position of the bugdoc was too large, and
turns out Word only works with vertical offsets if there is already a
horizontal offset.

For example open tdf98987.docx in Word, remove the left square shape,
notice how the other square shape jumps up due to no longer working with
a vertical offset (while the doc model vertical position of the shape is
unchanged).

Change our layout, so that in case the AddVerticalFrameOffsets
compatibility flag is on (which was added to emulate Word's behavior),
we also consider the horizontal offset before setting the vertical
offset.

Also improve the SwUiWriterTest2::testTdf122942() test that asserted doc
model positions, which are now different (needed so that at the end the
layout position visible to the user is unchanged).

(cherry picked from commit 27894be9)

Conflicts:
	sw/qa/extras/layout/layout.cxx
	sw/qa/extras/uiwriter/uiwriter2.cxx

Change-Id: I8ac451efbacefdd3578b3a578260e7b2060c16a6
Reviewed-on: https://gerrit.libreoffice.org/71128Reviewed-by: Aron Budea <aron.budea@collabora.com>
Tested-by: Aron Budea <aron.budea@collabora.com>