test/java/awt/dnd/MissingEventsOnModalDialog/MissingEventsOnModalDialogTest.java

rev 14031 : 8159690: [TESTBUG] Mark headful tests with @key headful.

Backport of 14851:980da45565c8 from jdk9.  542/842 hunks applied directly from
the patch. 44 I resolved manually.  The remaining hunks are for filenames that
do not exist in jdk8u.

@@ -41,10 +41,11 @@
 import java.awt.event.MouseAdapter;
 import java.awt.event.MouseEvent;
 
 /*
  * @test
+ * @key headful
  * @bug 8134917
  * @summary [macosx] JOptionPane doesn't receive mouse events when opened from a drop event
  * @author Alexandr Scherbatiy
  */
 public class MissingEventsOnModalDialogTest {