void setConfig(Long generation, boolean applyOnRestart, T config, PayloadChecksums payloadChecksums) {
        this.config.set(new ConfigState<>(true, generation, applyOnRestart, true, config, payloadChecksums));
    }
Called from {@link ConfigSubscriber} when the changed status of this config is propagated to the clients
config/src/main/java/com/yahoo/config/subscription/impl/ConfigSubscription.java