read at the wrong index in the scope information and we forgot to add
Context::MIN_CONTEXT_SLOTS to the index.

This fixes issue 24.
Review URL: http://codereview.chromium.org/1938

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@279 ce2b1a6d-e550-0410-aec6-3dcde31c8c00