Unoptimized code should already keep a reference to the SharedFunctionInfo,
let's use it instead of allocating a new object and prohibiting SharedFunctionInfo
specific optimizations.

Review URL: http://codereview.chromium.org/6706016

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@7467 ce2b1a6d-e550-0410-aec6-3dcde31c8c00