public function synchronize($locale)
    {
        $existingSystemZones = $this->manager->findSystemSlugs();

        $newZones = array();
        foreach ($this->registry->getConfigs() as $config) {
            if (false === in_array($config->getSlug(), $existingSystemZones)) {
                $newZones[] = $this->createZone($config);
            }
        }

        if (0 < count($newZones)) {
            $this->manager->save();

            foreach ($newZones as $zone) {
                $this->eventDispatcher->dispatch(BannerZoneEvents::CREATE, new BannerZoneEvent($zone, $locale));
            }
        }
    }