Bug 307747 EPartService doesn't render new parts
1. Have a part in a stack, it is the selected part. 2. Show another part in that stack using PartState.CREATE or PartState.VISIBLE. 3. The part should've been rendered. It is not.
bundles/org.eclipse.e4.ui.workbench/src/org/eclipse/e4/workbench/ui/internal/PartServiceImpl.java
application.getContext().runAndTrack(new IRunAndTrack() {
				public boolean notify(ContextChangeEvent event) {
					IObjectProvider provider = event.getContext();
					IEclipseContext eventsContext = ((ObjectProviderContext) provider).getContext();
					IEclipseContext childContext = (IEclipseContext) eventsContext
							.getLocal(IContextConstants.ACTIVE_CHILD);
					if (childContext != null) {
						rootContainer = (MElementContainer<MUIElement>) childContext
								.get(MWindow.class.getName());
					}
					return true;
				}
			}, null);
		}
	}
	@PreDestroy
	void preDestroy() {
		constructed = false;
		eventBroker.unsubscribe(selectedHandler);
	}
	private void firePartActivated(MPart part) {
		for (Object listener : listeners.getListeners()) {
			((IPartListener) listener).partActivated(part);
		}
	}
	private void firePartDeactivated(MPart part) {
		for (Object listener : listeners.getListeners()) {