another bit of sanity checking for queries: rewriting should be equal to cloning and rewriting

git-svn-id: https://svn.apache.org/repos/asf/lucene/java/trunk@770483 13f79535-47bb-0310-9956-ffa450edef68

src/test/org/apache/lucene/search/QueryUtils.java

@@ -91,6 +91,10 @@ public class QueryUtils {
         }
         checkExplanations(q1,s);
         checkSerialization(q1,s);
+        
+        Query q2 = (Query)q1.clone();
+        checkEqual(s.rewrite(q1),
+                   s.rewrite(q2));
       }
     } catch (IOException e) {
       throw new RuntimeException(e);