GitLab

Suppress failures on Retina Macs. These failures are kicking valid
jobs out of the commit queue. Tested suppression locally.

BUG=422803
TBR=zmo@chromium.org,bajones@chromium.org

Review URL: https://codereview.chromium.org/650773002

Cr-Commit-Position: refs/heads/master@{#299264}