Array.prototype.sort: Unchecked calls to hasOwnProperty and push and sort

BUG=v8:3537
LOG=
R=arv@chromium.org, wingo@igalia.com, yangguo@chromium.org

Review URL: https://codereview.chromium.org/555173002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24005 ce2b1a6d-e550-0410-aec6-3dcde31c8c00