Remove wrong overload.

This is a build fix against r161710.

TBR=abarth
BUG=305497

Review URL: https://codereview.chromium.org/68593002

git-svn-id: svn://svn.chromium.org/blink/trunk@161714 bbb929c8-8fbe-4397-9dbb-9b2b20218538