Add null arg check

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1384920 13f79535-47bb-0310-9956-ffa450edef68

lucene/core/src/java/org/apache/lucene/search/QueryWrapperFilter.java

@@ -39,6 +39,8 @@ public class QueryWrapperFilter extends Filter {
    * <code>query</code>.
    */
   public QueryWrapperFilter(Query query) {
+    if (query == null)
+      throw new NullPointerException("Query may not be null");
     this.query = query;
   }