Bug 334559 EPartService's part searching path may not include parts outside of the active perspective
tests/org.eclipse.e4.ui.tests/src/org/eclipse/e4/ui/tests/application/EPartServiceTest.java
MWindow window = BasicFactoryImpl.eINSTANCE.createWindow();
		application.getChildren().add(window);
		application.setSelectedElement(window);
		MPartDescriptor partDescriptor = org.eclipse.e4.ui.model.application.descriptor.basic.impl.BasicFactoryImpl.eINSTANCE
				.createPartDescriptor();
		partDescriptor.setAllowMultiple(multipleAllowed);
		partDescriptor.setElementId("partId");
		application.getDescriptors().add(partDescriptor);
		initialize(applicationContext, application);
		getEngine().createGui(window);
		EPartService partService = (EPartService) window.getContext().get(
				EPartService.class.getName());
		MPart createdPart = partService.createPart("partId");
		MPart shownPart = partService.showPart(createdPart, partState);
		assertNotNull(shownPart);
		assertEquals(createdPart, shownPart);
	}
	public void testShowPart_Part_MultipleNonexistent_TrueACTIVATE() {
		testShowPart_Part_MultipleNonexistent(true, PartState.ACTIVATE);
	}
	public void testShowPart_Part_MultipleNonexistent_FalseACTIVATE() {
		testShowPart_Part_MultipleNonexistent(false, PartState.ACTIVATE);
	}
	public void testShowPart_Part_MultipleNonexistent_TrueVISIBLE() {
		testShowPart_Part_MultipleNonexistent(true, PartState.VISIBLE);
	}
	public void testShowPart_Part_MultipleNonexistent_FalseVISIBLE() {
		testShowPart_Part_MultipleNonexistent(false, PartState.VISIBLE);
	}
	public void testShowPart_Part_MultipleNonexistent_TrueCREATE() {