Bug 298415 StackRenderer assumes the shell has not been disposed when forcing a re-layout
bundles/org.eclipse.e4.ui.workbench.renderers.swt/src/org/eclipse/e4/workbench/ui/renderers/swt/StackRenderer.java
String newName = (String) event
							.getProperty(UIEvents.EventTags.NEW_VALUE);
					item.setText(getLabel((MPart) uiElement, newName));
				} else if (UIEvents.UILabel.ICONURI.equals(attName)) {
					item.setImage(getImage(modelItem));
				} else if (UIEvents.UILabel.TOOLTIP.equals(attName)) {
					String newTTip = (String) event
							.getProperty(UIEvents.EventTags.NEW_VALUE);
					item.setToolTipText(newTTip);
				}
			}
		};
		eventBroker.subscribe(UIEvents.buildTopic(UIEvents.UILabel.TOPIC),
				itemUpdater);
		EventHandler dirtyUpdater = new EventHandler() {
			public void handleEvent(Event event) {
				Object objElement = event
						.getProperty(UIEvents.EventTags.ELEMENT);
				
				if (!(objElement instanceof MSaveablePart)) {
					return;
				}
				
				MSaveablePart uiElement = (MSaveablePart) objElement;
				
				MElementContainer<MUIElement> parent = uiElement.getParent();
				if (!(parent.getRenderer() == StackRenderer.this)) {
					return;
				}