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
window.getChildren().add(stack);
		window.setSelectedElement(stack);
		MPart part = BasicFactoryImpl.eINSTANCE.createPart();
		stack.getChildren().add(part);
		stack.setSelectedElement(part);
		initialize(applicationContext, application);
		getEngine().createGui(window);
		window.getContext().get(EPartService.class).hidePart(part, force);
		assertNull(stack.getSelectedElement());
	}
	public void testHidePart_Bug327044_True() {
		testHidePart_Bug327044(true);
	}
	public void testHidePart_Bug327044_False() {
		testHidePart_Bug327044(false);
	}
	private void testHidePart_Bug327765(boolean force) {
		MApplication application = ApplicationFactoryImpl.eINSTANCE
				.createApplication();
		MWindow window = BasicFactoryImpl.eINSTANCE.createWindow();
		application.getChildren().add(window);
		application.setSelectedElement(window);
		MPart part = BasicFactoryImpl.eINSTANCE.createPart();
		window.getSharedElements().add(part);
		MPerspectiveStack perspectiveStack = AdvancedFactoryImpl.eINSTANCE
				.createPerspectiveStack();
		window.getChildren().add(perspectiveStack);
		window.setSelectedElement(perspectiveStack);
		MPerspective perspectiveA = AdvancedFactoryImpl.eINSTANCE
				.createPerspective();