Merge "Merge "Notification footer shows when there are zero notifications"...

Merge "Merge "Notification footer shows when there are zero notifications" into sc-dev am: 5b0cad99 am: dc74de36" into sc-v2-dev-plus-aosp am: e8cc1083

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/15095468

Change-Id: I275ce4066daf5b2813968de746dda1f1f61ad5e8