Merge "Security fix for VPN app killable via lockscreen." into udc-dev am: a72e33cc

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/27145545



Change-Id: I2c106c46a657a861a8c3c9a9b153413527c1ae25
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>