R=kmillikin@chromium.org

BUG=v8:1782
TEST=mjsunit/debug-step-3.js

Review URL: http://codereview.chromium.org//8356001

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9708 ce2b1a6d-e550-0410-aec6-3dcde31c8c00