[Gardening] Rebaseline repaint-text-decoration-line.html

Needed after reverting r155719.

BUG=165462
TBR=pkasting@chromium.org

Review URL: https://codereview.chromium.org/22401005

git-svn-id: svn://svn.chromium.org/blink/trunk@155767 bbb929c8-8fbe-4397-9dbb-9b2b20218538