Prevents QS Header info clicks when it's hidden

Because the QS Header info views are not set to GONE but just alpha 0,
they could still be clicked when they were not visible. Makes sure that
the clicks are only passed when the views are visible to the user
(VISIBLE and all its parents VISIBLE and alpha>0).

Test: manual, tapping when collapsed and expanded
Fixes: 131408961
Change-Id: Icfb4cd8aca60710372bdff78dd9fb894bd6618d0