Auto-rebaseline for r177971

http://src.chromium.org/viewvc/blink?view=revision&revision=177971

BUG=380472
TBR=wangxianzhu@chromium.org

Review URL: https://codereview.chromium.org/385173010

git-svn-id: svn://svn.chromium.org/blink/trunk@178083 bbb929c8-8fbe-4397-9dbb-9b2b20218538