BUG=chromium:798964

Change-Id: I63c373ef3f27a3295fc79f5c82d78b5fd89a83da
Reviewed-on: https://chromium-review.googlesource.com/888752
Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#50925}