Merge "Re-add dividers when expanding notifications." into sc-dev am: e6b421ae am: 02fc1506 am: c4b4f1b4

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/15017662

Change-Id: I5a115aae4806de5c62cdda058f6b497f97c5c200