Bug 328946 Part activation history may return incorrect candidate if no placeholders could be found in a perspective
1. Window > Open Perspective > Other... > CVS Repository Exploring 2. Hide the 'CVS Repositories' view. 3. The 'History' view should become active, it is not.
tests/org.eclipse.e4.ui.tests/src/org/eclipse/e4/ui/tests/application/EPartServiceTest.java
public void testSwitchPerspective01() {
		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 perspectiveA = AdvancedFactoryImpl.eINSTANCE
				.createPerspective();
		perspectiveStack.getChildren().add(perspectiveA);
		perspectiveStack.setSelectedElement(perspectiveA);
		MPerspective perspectiveB = AdvancedFactoryImpl.eINSTANCE
				.createPerspective();
		perspectiveStack.getChildren().add(perspectiveB);
		initialize(applicationContext, application);
		getEngine().createGui(window);
		IEclipseContext windowContext = window.getContext();
		IEclipseContext perspectiveContextA = perspectiveA.getContext();
		assertEquals(perspectiveContextA, windowContext.getActiveChild());
		window.getContext().get(EPartService.class)
				.switchPerspective(perspectiveB);
		IEclipseContext perspectiveContextB = perspectiveB.getContext();
		assertEquals(perspectiveContextB, windowContext.getActiveChild());
	}
	public void testSwitchPerspective02() {
		MApplication application = ApplicationFactoryImpl.eINSTANCE
				.createApplication();