Merge "Add support for chain OTA generation." am: 4895d0a8b4 am: d5b6e875b0 am: da5830d990 am: e8e04e2b76

Original change: https://android-review.googlesource.com/c/platform/development/+/1776605

Change-Id: I9e8aa953790840346c16aa2aa17abead360aa60a