Bug 324230 NPE thrown when unrendering an MPartSashContainer that contains unrendered children
java.lang.NullPointerException at org.eclipse.e4.ui.workbench.renderers.swt.SashRenderer.hideChild(SashRenderer.java:317) at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.removeGui(PartRenderingEngine.java:517) at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.removeGui(PartRenderingEngine.java:528)
tests/org.eclipse.e4.ui.tests/src/org/eclipse/e4/ui/tests/workbench/PartRenderingEngineTests.java
assertEquals(
				"The presentation engine should have created the part and set it",
				partB.getWidget(), item2.getControl());
		
		stack.setSelectedElement(partB);
		assertEquals("Selecting the element should not have changed anything",
				partB.getWidget(), item2.getControl());
	}
	public void testToBeRenderedCausesSelectionChanges() {
		MApplication application = ApplicationFactoryImpl.eINSTANCE
				.createApplication();
		application.setContext(appContext);
		appContext.set(MApplication.class.getName(), application);
		MWindow window = BasicFactoryImpl.eINSTANCE.createWindow();
		application.getChildren().add(window);
		MPartStack stack = BasicFactoryImpl.eINSTANCE.createPartStack();
		window.getChildren().add(stack);
		MPart partA = BasicFactoryImpl.eINSTANCE.createPart();
		partA.setElementId("partA");
		partA.setContributionURI("platform:/plugin/org.eclipse.e4.ui.tests/org.eclipse.e4.ui.tests.workbench.SampleView");
		MPart partB = BasicFactoryImpl.eINSTANCE.createPart();
		partB.setElementId("partB");
		partB.setContributionURI("platform:/plugin/org.eclipse.e4.ui.tests/org.eclipse.e4.ui.tests.workbench.SampleView");
		stack.getChildren().add(partA);
		stack.getChildren().add(partB);
		wb = new E4Workbench(application, appContext);
		wb.createAndRunUI(window);
		CTabFolder tabFolder = (CTabFolder) stack.getWidget();
		assertEquals(0, tabFolder.getSelectionIndex());
		EPartService service = (EPartService) window.getContext().get(