Bug 328339 Part activation history seems to ignore detached windows
1. Detach a view. 2. Drag another view into said detached window. 3. Activate the two views alternatively. 4. Close one of them. 5. A part in the workbench window is activated instead of the other view in the detached window.
tests/org.eclipse.e4.ui.tests/src/org/eclipse/e4/ui/tests/application/EPartServiceTest.java
stackA.setSelectedElement(partA);
		MPlaceholder areaPlaceholder = AdvancedFactoryImpl.eINSTANCE
				.createPlaceholder();
		areaPlaceholder.setRef(area);
		area.setCurSharedRef(areaPlaceholder);
		perspective.getChildren().add(areaPlaceholder);
		MPartStack stackB = BasicFactoryImpl.eINSTANCE.createPartStack();
		area.getChildren().add(stackB);
		area.setSelectedElement(stackB);
		MPart partB1 = BasicFactoryImpl.eINSTANCE.createPart();
		stackB.getChildren().add(partB1);
		stackB.setSelectedElement(partB1);
		MPart partB2 = BasicFactoryImpl.eINSTANCE.createPart();
		stackB.getChildren().add(partB2);
		initialize(applicationContext, application);
		getEngine().createGui(window);
		EPartService partService = window.getContext().get(EPartService.class);
		partService.activate(partB1);
		partService.activate(partB2);
		partService.hidePart(partB2);
		assertEquals(partB1, stackB.getSelectedElement());
		assertEquals(partB1, partService.getActivePart());
		partService.hidePart(partB1);
		assertNull(stackB.getSelectedElement());
		assertEquals(partA, partService.getActivePart());
	}
	public void testHidePart_ActivationHistory13() {
		MApplication application = ApplicationFactoryImpl.eINSTANCE
				.createApplication();
		MWindow window = BasicFactoryImpl.eINSTANCE.createWindow();