private void initializeDefaultServices() {
serviceLocator.registerService(IWorkbenchPartSite.class, this);
final IHandlerService parentService = (IHandlerService) serviceLocator
.getService(IHandlerService.class);
final Expression defaultExpression = new ActivePartExpression(part);
final IHandlerService slave = new SlaveHandlerService(parentService,
defaultExpression);
serviceLocator.registerService(IHandlerService.class, slave);
final IContextService parentContextService = (IContextService) serviceLocator
.getService(IContextService.class);