orFactory that 
 allways returns null.
 <p> 
 This implementation may be useful for Solr installations in which neither 
 the <code><a href="../../../../../org/apache/solr/update/processor/DistributedUpdateProcessorFactory.html" title="class in org.apache.solr.update.processor"><code>DistributedUpdateProcessorFactory</code></a></code> nor any custom 
 implementation of <code><a href="../../../../../org/apache/solr/update/processor/DistributingUpdateProcessorFactory.html" title="interface in org.apache.solr.