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
eventBroker.unsubscribe(dirtyUpdater);
	}
	private String getLabel(MUILabel itemPart, String newName) {
		if (newName == null) {
			newName = ""; 
		}
		if (itemPart instanceof MDirtyable && ((MDirtyable) itemPart).isDirty()) {
			newName = '*' + newName;
		}
		return newName;
	}
	public Object createWidget(MUIElement element, Object parent) {
		Widget newWidget = null;
		if (!(element instanceof MPartStack) || !(parent instanceof Composite))
			return null;
		Composite parentComposite = (Composite) parent;
		
		
		
		
		int styleModifier = 0; 
		final CTabFolder ctf = new CTabFolder(parentComposite, SWT.BORDER
				| styleModifier);
		
		if (element.getTags().contains("newtablook")) { 
			ctf.setRenderer(new CTabRendering(ctf));
		}
		bindWidget(element, ctf);