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
handleSave();
		close();
	}
	/**
	 * Selects the page determined by <code>lastSuccessfulNode</code> in
	 * the page hierarchy.
	 */
	void selectCurrentPageAgain() {
		if (lastSuccessfulNode == null)
			return;
		getTreeViewer().setSelection(new StructuredSelection(lastSuccessfulNode));
		currentPage.setVisible(true);
	}
	/**
	 * Selects the saved item in the tree of preference pages.
	 * If it cannot do this it saves the first one.
	 */
	protected void selectSavedItem() {
		IPreferenceNode node = findNodeMatching(getSelectedNodePreference());
		if (node == null) {
			IPreferenceNode[] nodes = preferenceManager.getRoot().getSubNodes();
			if (nodes.length > 0)
				node = nodes[0];
		}
		if (node != null) {
			getTreeViewer().setSelection(new StructuredSelection(node));
			            
			getTreeViewer().getControl().setFocus();
		}
	}