Fix stray webkitpy unit test after r157385.

TBR=leviw@chromium.org
BUG=285572

Review URL: https://codereview.chromium.org/23541008

git-svn-id: svn://svn.chromium.org/blink/trunk@157389 bbb929c8-8fbe-4397-9dbb-9b2b20218538