With this change, we'll be able to discover how many type cells we
need at parse time, enabling future optimizations.

R=bmeurer@chromium.org

Review URL: https://codereview.chromium.org/141533004

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@18668 ce2b1a6d-e550-0410-aec6-3dcde31c8c00