Fix fdo#71423 - crash while editing Impress tables.
Fix fdo#71423 - crash while editing Impress tables.

Band-aid fix for this nasty crasher, seems sometimes the
family item is not found.

Change-Id: I7f78d59cbf2c9595ad512fa7a78370629924cd06

JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core