Fix some entrance animations for new QSHeaders

* Use qsVisible to indicate whether the shade is visible and the header
should be shown.
* When in lockscreen, use
LockscreenShadeTransitionController#dragProgress to track shade
expansion.
* Use this shade expansion to fade out the KeyguardStatusBarView

Test: manual, with and without flag, handheld and split shade
Test: atest SystemUITests
Bug: 202847414
Change-Id: Id57adff2fd75eba86832e8790816ef2d9afcf83d