change test to make sure everything is cleared first

git-svn-id: https://svn.apache.org/repos/asf/lucene/solr/trunk@613056 13f79535-47bb-0310-9956-ffa450edef68

client/java/solrj/test/org/apache/solr/client/solrj/LargeVolumeTestBase.java

@@ -39,6 +39,8 @@ public abstract class LargeVolumeTestBase extends SolrExampleTestBase
   
   public void testMultiThreaded() throws Exception {
     gserver = this.getSolrServer();
+    gserver.deleteByQuery( "*:*" ); // delete everything!
+    
     DocThread[] threads = new DocThread[threadCount];
     for (int i=0; i<threadCount; i++) {
       threads[i] = new DocThread( "T"+i+":" );