[flexiglass] Lockscreen scene returns to portrait mode.

Adds hydration of the 3 minimally required states in
NotificationShadeWindowController in order to get it to calculate the
correct screenOrientation value in adjustScreenOrientation.

This makes the lockscreen scene return to portrait mode, even if system
UI has been put in landscape mode while unlocked.

Not yet ready to treat the bug as fixed because the orientation change
button is showing and it's still possible to change the orientation to
landcape while on the lockscreen scene.

Bug: 335830658
Test: unit tests added
Test: manually verified that hydration still works the same for the
three added states (used printf debugging and compared calls of
setKeyguardShowing, setBouncerShowing, and setKeyguardOccluded with
flexiglass on or off)
Test: manually verified that returning to the lockscreen scene after
setting the device to landscape while unlocked, returns the device to
portrair mode
Flag: ACONFIG com.android.systemui.scene_container DEVELOPMENT

Change-Id: Iff145fcc8b57b6273a8b2ceb0caa602e93e3e721