Merge "Fixing notification background peeking from the bottom when expanding QS" into sc-dev am: 4c4ab603 am: 9a2f87c4

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/14980855

Change-Id: Ia631323b7879760f33c38853ac9e168d0f622970