Merge changes Ic88e8094,I4253bf4b,Iba4ebd3c,I943b6352,If88c0b08, ...

* changes:
  Made it easier to use updatable Animators
  Improved the interpolators of the icon appearing
  Modified the way icons merge into the shelf
  Fixed a potential heads up crash
  Fixed a bug where the notifications would close on back
  Bye bye veto button
  Only requiring 2 taps for accessibility on lock screen
  Fixed a bug where systemui could crash
  Introduced the visual stability manager
  Removing notifications always immediately when swiping them away