[DO NOT MERGE] Lockscreen/Shade upscaling

Aligns shade width and clock placement with latest UX specs. Removes
concept of a fixed stack scroller width in favor of margins that
adjust across various swXXXdp files. For phones, this means the shade
takes up the entire width, for larger portrait devices, a sizeable
margin, and for larger landscape devices, a smaller but visible
margin.

Remove unused code from KeyguardStatusView

Fixes: 214596698
Test: atest NotificationPanelViewControllerTest && Tested landscape
and portrait across all device categories
Change-Id: Ie384d88c9a2c20516c29dc49b9b7cc54de89917c

Change-Id: I82764f776aa43ba69d7bf93b76af111e20fd07b8