Merge "Specify --max_timestamp when calling brillo_update_payload." into...

Merge "Specify --max_timestamp when calling brillo_update_payload." into nyc-dr1-dev am: 21a26c98 am: 64e3da49 am: ed62f299 am: ea43cfbe  -s ours am: ca09e189  -s ours am: 96df5e3e  -s ours am: 51e5c768  -s ours
am: 9c9f2ad8  -s ours

Change-Id: I3bf4d80f1bcc9e3dc14ae5515d7e31bf2ac073aa