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
EPartService partService = window.getContext().get(EPartService.class);
		partService.activate(partA);
		partService.activate(partB);
		partService.hidePart(partB);
		assertEquals(partA, partService.getActivePart());
	}
	public void testHidePart_ActivationHistory_Bug327952_03() {
		MApplication application = ApplicationFactoryImpl.eINSTANCE
				.createApplication();
		MWindow window = BasicFactoryImpl.eINSTANCE.createWindow();
		application.getChildren().add(window);
		application.setSelectedElement(window);
		MPerspectiveStack perspectiveStack = AdvancedFactoryImpl.eINSTANCE
				.createPerspectiveStack();
		window.getChildren().add(perspectiveStack);
		window.setSelectedElement(perspectiveStack);
		MPerspective perspective = AdvancedFactoryImpl.eINSTANCE
				.createPerspective();
		perspectiveStack.getChildren().add(perspective);
		perspectiveStack.setSelectedElement(perspective);
		MPart partA = BasicFactoryImpl.eINSTANCE.createPart();
		window.getChildren().add(partA);
		window.setSelectedElement(partA);
		MWindow detachedWindow = BasicFactoryImpl.eINSTANCE.createWindow();
		perspective.getWindows().add(detachedWindow);
		MArea area = AdvancedFactoryImpl.eINSTANCE.createArea();
		detachedWindow.getChildren().add(area);
		detachedWindow.setSelectedElement(area);
		MPart partB = BasicFactoryImpl.eINSTANCE.createPart();
		area.getChildren().add(partB);