private void addHost(String hostname, String clusterName) throws AmbariException {
    clusters.addHost(hostname);
    setOsFamily(clusters.getHost(hostname), "redhat", "6.3");
    clusters.getHost(hostname).setState(HostState.HEALTHY);
    if (null != clusterName) {
      clusters.mapHostToCluster(hostname, clusterName);
    }
  }
Tests that when {@link ActionExecutionContext#isFutureCommand()} is set, invalid
hosts/components are still scheduled.

@throws Exception
ambari-server/src/test/java/org/apache/ambari/server/controller/AmbariCustomCommandExecutionHelperTest.java