Merge "Remove @hide usage and fix NetworkPolicy backup" am: 027b7e9604 am: 3ebe8bd26b am: 1a2183a68a

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/1978091

Change-Id: Ibd557eeceb1cfa07e74a77c29255a1f87995c91a