Fixes hotspot list transitions, update to use a single hotspot

Also updates background and button colors to match spec, removes
dependency on bouncycastle Arrays. Vastly simplifies ripple drawing.
Adds APIs for maximum ripple radius. Makes selectableItemBackground
bounded by default and adds an unbounded version and theme attribute.

BUG: 15315168
BUG: 15314684
BUG: 15314830
BUG: 15316768
BUG: 15333033
BUG: 15344050
Change-Id: Ib0619587ce78e43056b66571bae185e0f1613185