Treat the builtins object like other global objects (with

Treat the builtins object like other global objects (with
cells in old space for properties) and avoid allocating tons
of unused properties in new space when creating new contexts.
Review URL: http://codereview.chromium.org/151146

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2319 ce2b1a6d-e550-0410-aec6-3dcde31c8c00