Bug 48364 PreferenceDialog can reopen empty
20031209 When you close the Preferences dialog with an entry other than the default selected you will get an empty entry in the dialog when you reopen STEPS 1) Open the preferences dialog 2) Select the Appearances page 3) Close the dialog 4) Reopen - Workbench will be selected and the contents will be empty
bundles/org.eclipse.jface/src/org/eclipse/jface/preference/PreferenceDialog.java
private Composite pageContainer;
	/**
	 * The preference manager.
	 */
	private PreferenceManager preferenceManager;
	/**
	 * Preference store, initially <code>null</code> meaning none.
	 *
	 * @see #setPreferenceStore
	 */
	private IPreferenceStore preferenceStore;
	private boolean showingError = false;
	private Composite titleArea;
	private Color titleAreaColor;
	private Label titleImage;
	/**
	 * The tree viewer.
	 */
	private TreeViewer treeViewer;
	/**
	 * Creates a new preference dialog under the control of the given preference 
	 * manager.
	 *
	 * @param shell the parent shell
	 * @param manager the preference manager
	 */
	public PreferenceDialog(Shell parentShell, PreferenceManager manager) {
		super(parentShell);
		setShellStyle(getShellStyle() | SWT.RESIZE | SWT.MAX);
		preferenceManager = manager;