Bug 48400 [Dialogs] MessageDialog needs javadoc for returnCode == -1
org.eclipse.jface.dialogs.MessageDialog extends handleShellCloseEvent() and sets a returnCode of -1 when the dialog is closed without pressing a button (pressed esc key or clicked close box). This special returnCode needs to be commented in JavaDocs, since it is an unexpected result (and already caused problems). I suggest to ... - transform the comment for handleShellCloseEvent() into a JavaDoc comment - replace '-1' by SWT.DEFAULT or a new 'public static final int' constant - mention the special returnCode in MessageDialog's class JavaDoc
bundles/org.eclipse.jface/src/org/eclipse/jface/dialogs/MessageDialog.java
private Image titleImage;
	/**
	 * Image, or <code>null</code> if none.
	 */
	private Image image = null;
	
	/**
	 * The custom dialog area.
	 */
	private Control customArea;
/**
 * Create a message dialog.
 * Note that the dialog will have no visual representation (no widgets)
 * until it is told to open.
 * <p>
 * The labels of the buttons to appear in the button bar are supplied in this
 * constructor as an array. The <code>open</code> method will return the index
 * of the label in this array corresponding to the button that was pressed to 
 * close the dialog. If the dialog was dismissed without pressing a button (ESC, etc.)
 * then -1 is returned. Note that the <code>open</code> method blocks.
 * </p>
 *
 * @param parentShell the parent shell
 * @param dialogTitle the dialog title, or <code>null</code> if none
 * @param dialogTitleImage the dialog title image, or <code>null</code> if none
 * @param dialogMessage the dialog message
 * @param dialogImageType one of the following values:
 * <ul>
 *	<li> <code>MessageDialog.NONE</code> for a dialog with no image </li>
 *	<li> <code>MessageDialog.ERROR</code> for a dialog with an error image </li>