What icon pack is that?
Clix, available in Play Store. It's a keeper for me. Been using it for a while now and have no intention of changing. I've even backed up the .apk in case it ever disappears from the Store. If there's something you have that isn't themed, you can request for it to be done, or select an Icon from the pack. Usually the Icon is there, but because package names change it doesn't apply automatically. That's why some packs end up with three or more of the same Icon, each with a different Package name. Calendar and Clock particularly.
Clix uses icon mask, so any new apps without an icon in the pack will at least look themed, and you can usually find a suitable replacement from the existing Icons anyway.