Bug 304074 View toolbars don't go away when the view is closed
1. Run the compatibility layer. 2. Close the 'Package Explorer' view. 3. Its toolbar is still there.
bundles/org.eclipse.e4.ui.workbench.renderers.swt/src/org/eclipse/e4/workbench/ui/renderers/swt/StackRenderer.java
if (!(objElement instanceof MPart)) {
					return;
				}
				
				MPart uiElement = (MPart) objElement;
				
				MElementContainer<MUIElement> parent = uiElement.getParent();
				if (!(parent.getRenderer() == StackRenderer.this)) {
					return;
				}
				
				CTabItem item = findItemForPart(uiElement);
				if (item == null) {
					return;
				}
				Boolean dirtyState = (Boolean) event
						.getProperty(UIEvents.EventTags.NEW_VALUE);
				String text = item.getText();
				boolean hasAsterisk = text.charAt(0) == '*';
				if (dirtyState.booleanValue()) {
					if (!hasAsterisk) {
						item.setText('*' + text);
					}
				} else if (hasAsterisk) {
					item.setText(text.substring(1));
				}
			}
		};
		eventBroker.subscribe(UIEvents.buildTopic(UIEvents.Dirtyable.TOPIC,