Version 3.25.28.7 (merged r20375)

Store i18n meta data in hidden symbols instead of js accessible properties

BUG=354967
LOG=N
R=jochen@chromuim.org

Review URL: https://codereview.chromium.org/228283003

git-svn-id: https://v8.googlecode.com/svn/branches/3.25@20568 ce2b1a6d-e550-0410-aec6-3dcde31c8c00