Fix null pointer exception during device entry

Mapping the GONE to the SHADE keyguard state to match existing keyguard functionality. We see the scene change to GONE while isDeviceUnlocked is false due to a race condition and the map was missing an entry for the GONE scene.

Change-Id: I6fc8faed09993b79b83c5be4ea4af0e50cadbd8e
Fixes: 331827457
Fixes: 330582270
Test: manually, unlock and lock the device repeatedly with flexiglass enabled, it should not crash with a null pointer exception.
Flag: ACONFIG systemui com.android.systemui.scene_container DEVELOPMENT