Add and use PasswordMetrics#validateCredential() am: 811f091fff am: 5074551422 am: 770959fc9e am: 0221130bd7

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/2775377

Change-Id: I964d37a130f48cd7e32c81496a6695a8537ae947
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>