GitLab

Essentially a scroll node specific version of
http://crrev.com/2612093002 which was only omitted there
in the interest of incrementality.

BUG=674258
CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel

Review-Url: https://codereview.chromium.org/2623313003
Cr-Commit-Position: refs/heads/master@{#443348}