Merge changes I49c77e90,Id68b00fb,I1eaa617a,I14914db5,I405fc27a, ... into main

* changes:
  [flexiglass] Adds long-press settings menu support to lockscreen scene.
  [flexiglass] Removes lock button click handling from lockscreen scene.
  [flexiglass] Start with the legacy UI always hidden.
  [flexiglass] Makes Gone scene empty.
  [flexiglass] Send signals to the Falsing system.
  [flexiglass] Falsing system changes.