Make QS work in SceneContainer when locked

The special behavior of QS when opening from the lockscreen is provided
by `QSImpl` tracking `StatusBarState`. As we want to have the state
determined completely by the scene container system, we short circuit
the `mStatusBarState` value in `QSImpl` (tied to the flag) so it's
always SHADE (no special behavior).

Also, add squishiness and improve the animations from lockscreen and
from gone.

Test: atest QSImplTest QSSceneAdapterImplTest QSSceneAdapterTest
Fixes: 324622770
Flag: ACONFIG com.android.systemui.scene_container DEVELOPMENT
Change-Id: I96d9edc85cabce98b210320ed41e59076de37fe0