#2916 Sequence to loose work in editor

[Jeremy Faden]

1. Jython editor, write script but don't save.
2. Click New button
3. It correctly asks if you want to save
4. [esc], and it incorrectly doesn't save. Should return to editor.

[Jeremy Faden]

This is fixed. JOptionPane.showConfirmDialog returns JOptionPane.CLOSED_OPTION, so this is now mapped to JOptionPane.CANCEL_OPTION.