Do not display a link in Rietveld when a try job's buildnumber does not exist.
Do not display a link in Rietveld when a try job's buildnumber does not exist.

Grey try jobs (jobs which have not started yet) should not be a link.

BUG=430

Author: rmistry@chromium.org

Review: https://codereview.appspot.com/7908043/

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