Removing leftover code to sync accessibility and input focus.

1. We have decided to let the accessibility services take care
   for syncing accessibility and input focus. Some apps may
   move input focus when a given view takes input focus which
   dragging accessibility focus can lead to a loop in the
   focus traversal. This change removes some leftover sync
   code.

bug:6616861

Change-Id: I57cb44e315a386d13596794d3767b559e9ee3d99