@Experimental(feature=ExperimentalFeature.PATCH_UPGRADES)
  public Set<String> getSupportedServices() {
    return Collections.unmodifiableSet(m_services);
  }
Gets the services participating in the upgrade.

@return the set of supported services. This collection should never be
        empty.
ambari-server/src/main/java/org/apache/ambari/server/stack/upgrade/orchestrate/UpgradeContext.java