Auto-rebaseline for r178421

http://src.chromium.org/viewvc/blink?view=revision&revision=178421

BUG=383205
TBR=ccameron@chromium.org

Review URL: https://codereview.chromium.org/404363005

git-svn-id: svn://svn.chromium.org/blink/trunk@178701 bbb929c8-8fbe-4397-9dbb-9b2b20218538