Remove obsolete baseline for column-break-with-balancing.

This baseline accidentally survived an earlier reftest-conversion.

R=mstensho@opera.com
BUG=386567

Review URL: https://codereview.chromium.org/683483003

git-svn-id: svn://svn.chromium.org/blink/trunk@184470 bbb929c8-8fbe-4397-9dbb-9b2b20218538