Bug 36141 Misbehaving property page causes property dialog to fail to open
bundles/org.eclipse.jface/src/org/eclipse/jface/preference/PreferenceDialog.java
tree = new Tree(parent, SWT.BORDER);
		OpenStrategy eventAdapter = new OpenStrategy(tree);
		eventAdapter.addPostSelectionListener(new SelectionAdapter() {
			public void widgetSelected(final SelectionEvent event) {
				BusyIndicator.showWhile(tree.getDisplay(), new Runnable() {
					public void run() {
						Object data = event.item.getData();
						if (data instanceof IPreferenceNode) {
							if (!isCurrentPageValid()) {
								handleError();
							} else if (!showPage((IPreferenceNode) data)) {
								
								handleError();
							} else {
								
								currentTreeItem = (TreeItem) event.item;
							}
							
							tree.setFocus();
						}
					}
					private void handleError() {
						showPageFlippingAbortDialog();
						selectCurrentPageAgain();
						clearSelectedNode();
					}
				});
			}
		});
		eventAdapter.addSelectionListener(new SelectionAdapter() {