Some view not shown on the screen are reported for accessibility.

1. Some applications are keeping around visible views off screen
   to improve responsiveness by drawing them in layers, etc. While
   such a view is not visible on the screen the accessibility layer
   was reporting it since it was visible. Now the check is improved
   to verify whether the view is attached, is in visible window,
   is visible, and has a rectangle that is not clipped by its
   predecessors.

2. AccessibilityNodeInfo bounds in screen were not properly set
   since only the top left point was offset appropriately to
   take into account any predecessor's transformation matrix
   and the not transformed width and height were used. Now
   the bounds are properly offset.

bug:6291855

Change-Id: I244d1d9af81391676c1c9e0fe86cf4574ff37225