Bug 327933 Unrendering container with invalid selectedElement can cause target element to be unrendered
tests/org.eclipse.e4.ui.tests/src/org/eclipse/e4/ui/tests/workbench/PartRenderingEngineTests.java
wb = new E4Workbench(application, appContext);
		wb.createAndRunUI(window);
		SampleView view = (SampleView) part.getObject();
		assertFalse(view.isDestroyed());
		perspectiveStack.setSelectedElement(perspectiveB);
		placeholderB.setToBeRendered(false);
		assertFalse(view.isDestroyed());
		assertNotNull(part.getContext().getParent());
		assertEquals(perspectiveA.getContext(), part.getContext().getParent());
	}
	public void testRemoveGuiBug324228_3() {
		MApplication application = ApplicationFactoryImpl.eINSTANCE
				.createApplication();
		MWindow window = BasicFactoryImpl.eINSTANCE.createWindow();
		application.getChildren().add(window);
		application.setSelectedElement(window);
		MPartStack partStack = BasicFactoryImpl.eINSTANCE.createPartStack();
		window.getSharedElements().add(partStack);
		MPart part = BasicFactoryImpl.eINSTANCE.createPart();
		part.setContributionURI("platform:/plugin/org.eclipse.e4.ui.tests/org.eclipse.e4.ui.tests.workbench.SampleView");
		partStack.getChildren().add(part);
		MPerspectiveStack perspectiveStack = AdvancedFactoryImpl.eINSTANCE
				.createPerspectiveStack();
		window.getChildren().add(perspectiveStack);
		window.setSelectedElement(perspectiveStack);
		MPerspective perspectiveA = AdvancedFactoryImpl.eINSTANCE
				.createPerspective();
		perspectiveA.setElementId("perspectiveA"); 
		perspectiveStack.getChildren().add(perspectiveA);
		perspectiveStack.setSelectedElement(perspectiveA);