Bug 334644 Cannot manually un/render a window that's directly under the application
Setting the 'toBeRendered' flag for a window that's a direct child of an application does nothing. The workaround is to manually de/construct it via the IPresentationEngine.
tests/org.eclipse.e4.ui.tests/src/org/eclipse/e4/ui/tests/workbench/PartRenderingEngineTests.java
protected IEclipseContext appContext;
	protected E4Workbench wb;
	@Override
	protected void setUp() throws Exception {
		appContext = E4Application.createDefaultContext();
		appContext.set(E4Workbench.PRESENTATION_URI_ARG,
				PartRenderingEngine.engineURI);
	}
	@Override
	protected void tearDown() throws Exception {
		if (wb != null) {
			wb.close();
		}
		appContext.dispose();
	}
	public void testCreateViewBug298415() {
		final MWindow window = createWindowWithOneView("Part Name");
		MApplication application = ApplicationFactoryImpl.eINSTANCE
				.createApplication();
		application.getChildren().add(window);
		application.setContext(appContext);
		appContext.set(MApplication.class.getName(), application);
		wb = new E4Workbench(application, appContext);
		wb.createAndRunUI(window);
		MPartSashContainer container = (MPartSashContainer) window
				.getChildren().get(0);
		MPartStack stack = (MPartStack) container.getChildren().get(0);
		MPart part = (MPart) stack.getChildren().get(0);
		IPresentationEngine renderer = (IPresentationEngine) appContext