public void setClusterStateVersionBundleSent(ClusterStateBundle stateBundle) {
        if (stateBundle == null) {
            throw new Error("Should not clear info for last version sent");
        }
        if (clusterStateVersionBundleSent.containsKey(stateBundle.getVersion())) {
            throw new IllegalStateException("We have already sent cluster state version " + stateBundle.getVersion() + " to " + node);
        }
        clusterStateVersionBundleSent.put(stateBundle.getVersion(), stateBundle);
    }
Sets the wanted state. The wanted state is taken as UP if a null argument is given
clustercontroller-core/src/main/java/com/yahoo/vespa/clustercontroller/core/NodeInfo.java