Merge changes from topic "heads_up_redesign" into pi-dev

* changes:
  Added new appear and disappear animations for heads up
  Polished the heads up experience
  Removed the heads up scrim and replaced it with more elevation
  Insetting heads up notifications
  Ensured that the heads-up notifications are always rounded

diff --cc packages/SystemUI/src/com/android/systemui/statusbar/NotificationData.java
Simple merge