Match Clock properties from xml

We match the properties from the qs_combined_header xml for Clock. We
also use unbounded wrap content, to make sure the clock will have enough
room when it expands.

Test: manual, expand from QQS to QS
Flag: com.android.systemui.scene_container
Fixes: 438431529
Change-Id: I553b27c1f0f5c69ee795aa8bc2b876744967e9d7