Merge "Add a gray debug line to NSSL to show the keyguard padding." into sc-v2-dev am: 0a1e89e7 am: b2bd7970

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/15178166

Change-Id: I178b860476bb5c0b67f046b3b46d245686ad22c1