Landing patch by Ryan Dahl.

TBR=vegorov@chromium.org

Original review: http://codereview.chromium.org/6667030/

Review URL: http://codereview.chromium.org/6667031

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@7142 ce2b1a6d-e550-0410-aec6-3dcde31c8c00