Swipe up to home animation changes.

* Tracks either the top or bottom of the rect for the fling/spring in the
Y direction.
- This allows us to have the icon always animate downwards.

* Scales the spring velocity for the Y component.

Bug: 124510042
Change-Id: I47571f906c8aa1beca4dd703d67d013ab6a1161f
4 files changed