Bug 1036787 SimCard Text Not Reflecting On Language Change

Do we need to assert against localized strings here (and below)? `mozL10n.get` mock will return just the key passed to the function when it's a simple l10n id ([Reference](https://github.com/mozilla-b2g/gaia/blob/master/apps/communications/contacts/test/unit/mock_l10n.js#L13)).