Hold the information if L10n was ready before.
Merge branch 'CB-7515_fixl10n_read_event'
CB-7548 [BlackBerry10] Allow any numeric type as date in dateToString method.
CB-6490 [BlackBerry10] Use hyphen instead of underscore in getLocaleName().
[BlackBerry10] Re-implement getPreferredLanguage() and getLocaleName().