Bug 144556 [Dialogs] TitleAreaDialog fails to properly recreate when an instance is reopened
When a TitleAreaDialog is created, opened, closed and opened again on the same instance the messageArea is not properly checked against disposal when it is accessed in setWarningMessage throwing an SWTException for disposed when the message area is updated the second time the dialog is opened.
bundles/org.eclipse.jface/src/org/eclipse/jface/dialogs/TitleAreaDialog.java
childLayout.marginWidth = 0;
        childLayout.verticalSpacing = 0;
        workArea.setLayout(childLayout);
        Control top = createTitleArea(contents);
        resetWorkAreaAttachments(top);
        workArea.setFont(JFaceResources.getDialogFont());
        
        initializeDialogUnits(workArea);
        
        dialogArea = createDialogArea(workArea);
        buttonBar = createButtonBar(workArea);
        return contents;
    }
    /**
     * Creates and returns the contents of the upper part of this dialog (above
     * the button bar).
     * <p>
     * The <code>Dialog</code> implementation of this framework method creates
     * and returns a new <code>Composite</code> with no margins and spacing.
     * Subclasses should override.
     * </p>
     * 
     * @param parent
     *            The parent composite to contain the dialog area
     * @return the dialog area control
     */
    protected Control createDialogArea(Composite parent) {
        
        Composite composite = new Composite(parent, SWT.NONE);
        GridLayout layout = new GridLayout();