Always call legacy performLongClick()

Adding performLongClick(x,y) broke compatibility for widgets that
overrode the no-arg performLongClick() and expected to receive a call.
This CL ensures that the no-arg method is called and the (x,y) data is
preserved for use in the default implementation.

Bug: 25411884
Change-Id: Ib0a3fb02d4c08ef64ce3a7165aa83bf0688aa50e