Remove cros specific bits from aosp am: 5c1451f87b am: f02d05e09a

Original change: https://android-review.googlesource.com/c/platform/system/update_engine/+/1512483

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: I9e49173bbfa2decfd8652c8da5e24eafdc02b450