fdo#80284: Write test for this first.

Change-Id: I2fe455fc627e4b358507b58f08a3198ac62edad0
fdo#80284: Avoid broadcasting during cell delete & shift.

Broadcasting it here and marking formula cells dirty prevents them
from being entered into the formula tree at the end.  They get marked
"postponed dirty" during reference update, and are supposed to be
set dirty at the end.

Change-Id: I65977300ee4ee26b6166d170acd2145abcbbf288