(Keep track of which maps are associated with prototype objects so we can tune the fast-case vs. hash map heuristics accordingly.).
Reverting because the dict-mode to fast case transformation loses the iteration order information.
Review URL: https://chromiumcodereview.appspot.com/10448097

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11685 ce2b1a6d-e550-0410-aec6-3dcde31c8c00