[flexiglass] Changes to the bouncer scene when becomes non-interactive.

When the device becomes uninteractive, a change to the lockscreen scene
happens. This fixes an edge case where, despite the previous CL in this
chain, it's possible to switch to the bouncer scene in AOD mode if the
flinging up from the lockscreen to the bouncer scene happens right while
the transition into AOD occurs.

Fix: 330474509
Test: unit test added
Test: manually verified that what worked previously (fling up quickly
while entering AOD) doesn't work anymore - even if the bouncer scene
shows up, it goes away and we end up on the lockscreen scene in AOD.
Flag: ACONFIG com.android.systemui.scene_container DEVELOPMENT

Change-Id: I53ea810d6a825121f7e5496027d26705f7b3b00f