Leaving this out can cause crashes when running with --heap-stats (but this is only used when reporting heap statistics, so this is not a stability issue).
Review URL: http://codereview.chromium.org/7647018

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8932 ce2b1a6d-e550-0410-aec6-3dcde31c8c00