Merge "Kill off callback reference as soon as credential is verified" into...

Merge "Kill off callback reference as soon as credential is verified" into rvc-dev am: 998df4f3 am: 13dbfb28 am: e099486f

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/11721688

Change-Id: I4ec796548fd8acede93329e294d2cdb9ff4a319b