Bug 304211 StackRenderer does not set eagerly created controls to the item
Right-clicking on a Java element and then using 'Open Declaration' opens an editor on the specified file but its content is not shown. Switching tabs or selecting items in the 'Outline' view does _not_ help. Seems to be calling IWorkbenchPage's APIs properly. No idea yet as to what's going on over here.
bundles/org.eclipse.e4.ui.workbench.renderers.swt/src/org/eclipse/e4/workbench/ui/renderers/swt/StackRenderer.java
CTabItem item = findItemForPart(uiElement);
				if (item == null)
					return;
				String attName = (String) event
						.getProperty(UIEvents.EventTags.ATTNAME);
				if (UIEvents.UILabel.LABEL.equals(attName)) {
					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);
		dirtyUpdater = new EventHandler() {
			public void handleEvent(Event event) {
				Object objElement = event
						.getProperty(UIEvents.EventTags.ELEMENT);
				
				if (!(objElement instanceof MPart)) {
					return;
				}
				
				MPart uiElement = (MPart) objElement;