src/share/classes/javax/swing/plaf/basic/BasicComboBoxEditor.java

*** 127,136 ****
--- 127,137 ----
  
      public void removeActionListener(ActionListener l) {
          editor.removeActionListener(l);
      }
  
+     @SuppressWarnings("serial") // Superclass is not serializable across versions
      static class BorderlessTextField extends JTextField {
          public BorderlessTextField(String value,int n) {
              super(value,n);
          }