DevTools: fix go-to-line dialog after migrating to post-key-down handling.

R=lushnikov@chromium.org

Review URL: https://codereview.chromium.org/131103005

git-svn-id: svn://svn.chromium.org/blink/trunk@165472 bbb929c8-8fbe-4397-9dbb-9b2b20218538