When getting properties for the global object proxy the properties from the global object are returned.

Script objects now have handles and are serialized by reference.

Added special handling for NaN.
Review URL: http://codereview.chromium.org/18445

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@1116 ce2b1a6d-e550-0410-aec6-3dcde31c8c00