Bug 1092930 - [Keyboard] No alternate indicator for Chinese period

That bug tries to do something more -- for example, when we're generating the URL layout, we hardcode a key object for '/' such as in https://github.com/mozilla-b2g/gaia/blob/master/apps/keyboard/js/keyboard/layout_manager.js#L322-L329 . I'd like to do something in that bug such we can simply `spaceKeyRow.splice(spaceKeyCount, 0, LayoutNormalizer.normalizeKey({value: '/'}, page))`; . 

I think that bug probably depends on this bug since period and comma keys would only be correctly normalized with `className="alternate-indicator"` with this bug's fix.