Merge "FRR follow-up: address comments in AuthenticationStatsPersister" into udc-qpr-dev am: 83cfc03653

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/24516053

Change-Id: I042e75ab1603691d9d24a049c1ecd7b3b823d79f
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>