Fix NestedScrollView intercepting touches when it shouldn't

Caused by NestedScrollView not calling springBack() like it's
framework cousin. This means that the scroller still thinks it
is running and makes NSV intercept the next DOWN -> UP touch
event cycle.

BUG: 23340105
Change-Id: I5a036b27c6c2161f7932ee6c3ad3ec180b1e12f3
4 files changed