Add dimensions for notification channel panel am: 42ac382af5

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Settings/+/21334700

Change-Id: Ifccc813cdfc93c795ec0938131adeee402f44b2f
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>