Bug 329482 Uninstantiated part may be rendered when closing another part in the same stack
1. Activate the 'Javadoc' view. 2. Activate the 'Package Explorer' view. 3. Shutdown. 4. Restart. 5. Ctrl+3 > Properties 6. Hide the 'Properties' view. 7. Now the 'Problems' view is the selected element. It should be the 'Javadoc' view.
tests/org.eclipse.e4.ui.tests/src/org/eclipse/e4/ui/tests/application/EPartServiceTest.java
window.getChildren().add(partA);
		window.setSelectedElement(partA);
		MPart partB = BasicFactoryImpl.eINSTANCE.createPart();
		partB.setContributionURI("platform:/plugin/org.eclipse.e4.ui.tests/org.eclipse.e4.ui.tests.application.ClientEditor");
		window.getChildren().add(partB);
		initialize(applicationContext, application);
		getEngine().createGui(window);
		ClientEditor editorB = (ClientEditor) partB.getObject();
		assertFalse(editorB.wasFocusCalled());
		EPartService partService = window.getContext().get(EPartService.class);
		partService.activate(partB);
		assertTrue(editorB.wasFocusCalled());
	}
	public void testActivate_ChildWindow() {
		MApplication application = ApplicationFactoryImpl.eINSTANCE
				.createApplication();
		MWindow window = BasicFactoryImpl.eINSTANCE.createWindow();
		application.getChildren().add(window);
		application.setSelectedElement(window);
		MPart partA = BasicFactoryImpl.eINSTANCE.createPart();
		window.getChildren().add(partA);
		window.setSelectedElement(partA);
		MWindow detachedWindow = BasicFactoryImpl.eINSTANCE.createWindow();
		window.getWindows().add(detachedWindow);
		MPart partB = BasicFactoryImpl.eINSTANCE.createPart();
		detachedWindow.getChildren().add(partB);
		detachedWindow.setSelectedElement(partB);
		initialize(applicationContext, application);
		getEngine().createGui(window);
		EPartService partService = window.getContext().get(EPartService.class);