Roll infra/appengine/swarming to f07a565b648.
Roll infra/appengine/swarming to f07a565b648.

TBR=vadimsh@chromium.org
BUG=

Review URL: https://codereview.chromium.org/644723004

nicko96/Chrome-Infra,nicko96/Chrome-Infra,nicko96/Chrome-Infra,nicko96/Chrome-Infra,nicko96/Chrome-Infra