Ability to upcast into arrays and return the first obj

Hello sho, 

Please review the following commits I made in branch 'jeremy-arrays'.

e8a72a28f42ab0654bb6c1be3dc42ab9e2bdd5fc (2013-02-03 00:21:28 -0800)
Adding ability to upcast objects into arrays and return the first object consistently

8e0905e27f736d774de0bfa6331f62cb6dc832c3 (2013-02-02 23:33:19 -0800)
Removing profiling on test/scope.js because it's hanging the test

R=sho