Temporarily truncate the length of the likely_failures list.
Temporarily truncate the length of the likely_failures list.

R=hinoka@chromium.org, jparent@chromium.org
BUG=462762

Review URL: https://codereview.chromium.org/966913004

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