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
partService.activate(partA);
		partService.activate(partB);
		partService.activate(partC);
		partService.activate(partA);
		partService.activate(partB);
		partService.hidePart(partB);
		assertEquals(partA, partService.getActivePart());
	}
	public void testHidePart_ActivationHistory_Bug327952_02() {
		MApplication application = ApplicationFactoryImpl.eINSTANCE
				.createApplication();
		MWindow window = BasicFactoryImpl.eINSTANCE.createWindow();
		application.getChildren().add(window);
		application.setSelectedElement(window);
		MWindow detachedWindow = BasicFactoryImpl.eINSTANCE.createWindow();
		window.getWindows().add(detachedWindow);
		MPart partA = BasicFactoryImpl.eINSTANCE.createPart();
		window.getChildren().add(partA);
		window.setSelectedElement(partA);
		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);
		partService.activate(partA);
		partService.activate(partB);
		partService.hidePart(partB);
		assertEquals(partA, partService.getActivePart());
	}