7094099: DropDown List of JComboBox detached

Reviewed-by: alexp, dcherepanov

src/share/classes/javax/swing/MenuSelectionManager.java

 /*
- * Copyright (c) 1997, 2011, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2014, 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
@@ -30,6 +30,7 @@ import java.awt.event.*;
 import javax.swing.event.*;
 
 import sun.awt.AppContext;
+import sun.swing.SwingUtilities2;
 
 /**
  * A MenuSelectionManager owns the selection in menu hierarchy.
@@ -60,6 +61,12 @@ public class MenuSelectionManager {
             if (msm == null) {
                 msm = new MenuSelectionManager();
                 context.put(MENU_SELECTION_MANAGER_KEY, msm);
+
+                // installing additional listener if found in the AppContext
+                Object o = context.get(SwingUtilities2.MENU_SELECTION_MANAGER_LISTENER_KEY);
+                if (o != null && o instanceof ChangeListener) {
+                    msm.addChangeListener((ChangeListener) o);
+                }
             }
 
             return msm;

src/share/classes/sun/swing/SwingUtilities2.java

 /*
- * Copyright (c) 2002, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2002, 2014, 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
@@ -81,6 +81,9 @@ public class SwingUtilities2 {
     public static final Object LAF_STATE_KEY =
             new StringBuffer("LookAndFeel State");
 
+    public static final Object MENU_SELECTION_MANAGER_LISTENER_KEY =
+            new StringBuffer("MenuSelectionManager listener key");
+
     // Maintain a cache of CACHE_SIZE fonts and the left side bearing
      // of the characters falling into the range MIN_CHAR_INDEX to
      // MAX_CHAR_INDEX. The values in fontCache are created as needed.