Accessibility focus on temporary detached view not cleared.

1. When a view that has accessibility focus is temporary detached
   we try to draw the focus highlight and crash. Since the detached
   view will be modified and then either attached or detached from
   the window we should not keep accessibility focus on a temporary
   detached view. Otherwise, we may have a scenario where the user
   thinks he is in one item scroll acound and being in completely
   different item because of the view being recycled but the user
   has no clue.

2. Clearing accessibility focus when the view is removed from the
   parent as opposed as when it is detached from the window. Since
   we may have transitioning views for removal we do not want
   accessibility focus on such views during the anumation.

bug:6457339

Change-Id: I62287a089ec6850fb1d691ae26dea54e1da39c94