Screenshot swipe-dismiss polish

- Allow swiping on any part of the UI (+ a 12-dp border)
- All parts of the UI move together (in the 'start' direction)
- In cases where the actions are scrollable, scrolls the action
bar first, then moves to dragging the UI once the actions are
fully scrolled
- Resets the timeout on any user interaction (touch event)

- Fixes smart action visibility
- Fixes focus on touch_outside

Bug: 157223526
Test: manual
Change-Id: Ide8a4bf80964e301b48140eb1201df9b4a9e27f8