Fix overview scroll triggering haptics on swipe up gesture

Add an extra check to the PagedView, before triggering the haptic
callback, to avoid triggering this when the scroll happens
outside an actual scroll action (e.g. some setter methods that update
the scroll state).

This was triggered on some calls to setCurrentPage, that was
snapping the current scrolled page and triggering the
View.onScrollChanged method.

Fix: 201237536
Test: manual
Change-Id: I9b29981dba408493c78873aea42d8615ea7573a0