Bug 218360 [Servicability] Fix places that pop up message dialogues under ISafeRunnable
bundles/org.eclipse.jface/src/org/eclipse/jface/preference/PreferenceDialog.java
/**
	 * The Composite in which a page is shown.
	 */
	private Composite pageContainer;
	/**
	 * The preference manager.
	 */
	private PreferenceManager preferenceManager;
	/**
	 * Flag for the presence of the error message.
	 */
	private boolean showingError = false;
	/**
	 * Preference store, initially <code>null</code> meaning none.
	 * 
	 * @see #setPreferenceStore
	 */
	private IPreferenceStore preferenceStore;
	private Composite titleArea;
	/**
	 * The tree viewer.
	 */
	private TreeViewer treeViewer;
	
    private ListenerList pageChangedListeners = new ListenerList();
    /**
     *  Composite with a FormLayout to contain the title area
     */
    Composite formTitleComposite;
	private ScrolledComposite scrolled;