Accessibility active window not updated on time.

1. The active window is the one the user is touching or the one
   that has input focus. It has to be made current immediately
   after the user has stopped touching the screen because if the
   user types with the IME he should get a feedback for the
   letter typed in the text view which is in the input focused
   window. Note that we always deliver hover accessibility events
   (they are a result of user touching the screen) so change of
   the active window before all hover accessibility events from
   the touched window are delivered is fine.

bug:7296890

Change-Id: I1ae87c8419e2f19bd8eb68de084c7117c66894bc