Turn on i18n support by default

BUG=v8:2745
R=danno@chromium.org

Review URL: https://codereview.chromium.org/23003028

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@16783 ce2b1a6d-e550-0410-aec6-3dcde31c8c00