Adding SecureTouchListener to drop suspicious touches

Added a touch listener that will drop touches if the window receiving the
touch was partly or wholly obscured by another window sitting on top of
it.

Test: N/A

Bug: 35056974
Change-Id: I4a7273bd12ae10a65c39e6b4f1c6641266dd21e4
(cherry picked from commit 395b58d6)