Revert "Prevent unwanted height processing: no UITableView.beginUpdates/endUpdates with empty diff"
Revert "Prevent unwanted height processing: no UITableView.beginUpdates/endUpdates with empty diff"

This reverts commit 1c08885d5d7baa445415e934385d8aa721586678.

tonyarnold/Differ,tonyarnold/Differ,tonyarnold/Differ,tonyarnold/Differ