This lands: http://codereview.chromium.org/160556.

TBR=piman@chromium.org
Review URL: http://codereview.chromium.org/160634

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2622 ce2b1a6d-e550-0410-aec6-3dcde31c8c00