Merge "Add support for app-generated attestation keys." am: 50a66e39cd am: 2da3a280d2

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/1584474

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: Iad2f426ed43fdb9b4e62c81902d9f7ff8e936535