7161759: TEST_BUG: java/awt/Frame/WindowDragTest/WindowDragTest.java fails to compile, should be modified

Added @build Util jtreg tag

Reviewed-by: serb, alexsch

jdk/test/java/awt/Frame/WindowDragTest/WindowDragTest.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2012, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012, 2013, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -23,10 +23,11 @@
 
 /*
   @test
-  @bug 7128738
+  @bug 7128738 7161759
   @summary dragged dialog freezes system on dispose
   @author Oleg Pekhovskiy: area=awt.toplevel
   @library ../../regtesthelpers
+  @build Util
   @run main WindowDragTest
 */