writerfilter: DOCX import: fix handling of w:hideMark vs. w:vMerge

The problem is that Writer's layout can't handle the case where cells
are vertically merged and the last row has a fixed height; the vertically
merged cell will grow up to the height of the other cells in the non-
fixed rows plus the fixed row height, but no larger.

So for now, avoid setting fixed row heights in this case.

(regression from d1278ef4)

Change-Id: Iac3689e0bb0d5b8a62115ca0fb1f2c553a6e6bbc

writerfilter/source/dmapper/DomainMapperTableHandler.cxx

@@ -875,8 +875,12 @@ CellPropertyValuesSeq_t DomainMapperTableHandler::endTableGetCellProperties(Tabl
 bool lcl_hideMarks(PropertyMapVector1& rCellProperties)
 {
     for (PropertyMapPtr & p : rCellProperties)
-        if (!p->isSet(PROP_CELL_HIDE_MARK))
+    {
+        // if anything is vertically merged, the row must not be set to fixed
+        // as Writer's layout doesn't handle that well
+        if (!p->isSet(PROP_CELL_HIDE_MARK) || p->isSet(PROP_VERTICAL_MERGE))
             return false;
+    }
     return true;
 }