Merge "Add support for app-generated attestation keys." am: 50a66e39 am: 2da3a280 am: bbdb4d9e am: c418d4ef am: 78248ec3

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

Change-Id: I55d5ee3bf3987e3dcde64a479bfcea1574c97561