The flag is already on by default

R=clemensh@chromium.org

Change-Id: Ie4ede8191336a102cab9d7f972a3d10a15d1a54d
Reviewed-on: https://chromium-review.googlesource.com/456287Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Commit-Queue: Andreas Haas <ahaas@chromium.org>
Cr-Commit-Position: refs/heads/master@{#43963}