Centering Animation with glyph stepping

This is a basic implementation that is functional and good enough for
now, but there seems to be some inconsistency being introduced from
deriving the end position from the start position, current position,
and interpolatin progress. While the animation works, it's not quite to
spec, and we'll likely need to do another pass once some infrastructure
STL work like I9b8498972b57b35c7066c95c1825daa499efacd5 is complete.

Bug: 418824686
Test: Checked clock centering animation
Flag: com.android.systemui.scene_container
Change-Id: Iacf9195001291f85093b2ac0de58ac380c81b01b