Bug 307747 EPartService doesn't render new parts
1. Have a part in a stack, it is the selected part. 2. Show another part in that stack using PartState.CREATE or PartState.VISIBLE. 3. The part should've been rendered. It is not.
tests/org.eclipse.e4.ui.tests/src/org/eclipse/e4/ui/tests/application/EPartServiceTest.java
assertEquals(null, partB2.getContext());
		MPart shownPart = partService.showPart("partA2",
				EPartService.PartState.CREATE);
		assertTrue(partService.isPartVisible(partA1));
		assertTrue(partService.isPartVisible(partB1));
		assertEquals(partA1, partService.getActivePart());
		assertEquals(shownPart, partA2);
		assertNotNull(
				"The part should have been created so it should have a context",
				partA2.getContext());
		assertEquals(
				"This part has not been instantiated yet, it should have no context",
				null, partB2.getContext());
		shownPart = partService.showPart("partB2",
				EPartService.PartState.CREATE);
		assertTrue(partService.isPartVisible(partA1));
		assertTrue(partService.isPartVisible(partB1));
		assertEquals(partA1, partService.getActivePart());
		assertEquals(shownPart, partB2);
		assertNotNull(
				"The part should have been created so it should have a context",
				partA2.getContext());
		assertNotNull(
				"The part should have been created so it should have a context",
				partB2.getContext());
	}
	public void testShowPart_Id_CREATE2() {
		MApplication application = MApplicationFactory.eINSTANCE
				.createApplication();
		MWindow window = MApplicationFactory.eINSTANCE.createWindow();