fdo#71491: Write test for this.

Change-Id: I20de3d5c3c254b2ce96678553d91492dc95e2c39
fdo#71491: Adjust reference during undo of drag-n-drop of cell range.

Also with this commit, the signature of SvtListener::Notify() changes,
by dropping the first argument which nobody uses.  This change was necessary
in order to call it directly without needing to pass any broadcaster instance.

Change-Id: I6a1e97f0fb1e070d1d8f7db614690b04c9e8024e