Fix some organization of view model

Also, make sure that going back when editing is not a valid destination
to close QS.

Test: manual, back when editing
Test: atest QuickSettingsShadeSceneViewModelTest
Flag: com.android.systemui.qs_ui_refactor
Flag: com.android.systemui.dual_shade
Bug: 331598956

Change-Id: If176f62f8ab3fc346aba219047c44ccee0616309
5 files changed