Bug 315907 Render menus on SWT.Show
bundles/org.eclipse.e4.ui.workbench.swt/src/org/eclipse/e4/ui/internal/workbench/swt/PartRenderingEngine.java
if (element instanceof MContext) {
			MContext ctxt = (MContext) element;
			IEclipseContext lclContext = ctxt.getContext();
			if (lclContext != null) {
				IEclipseContext parentContext = lclContext.getParent();
				Object child = parentContext
						.get(IContextConstants.ACTIVE_CHILD);
				if (child == lclContext) {
					parentContext.set(IContextConstants.ACTIVE_CHILD, null);
				}
				ctxt.setContext(null);
				if (lclContext instanceof IDisposable) {
					((IDisposable) lclContext).dispose();
				}
			}
		}
	}
	protected Object createWidget(MUIElement element, Object parent) {
		AbstractPartRenderer renderer = getRenderer(element, parent);
		if (renderer != null) {
			Object newWidget = renderer.createWidget(element, parent);
			if (newWidget != null) {
				renderer.bindWidget(element, newWidget);
				return newWidget;
			}
		}
		return null;
	}
	private AbstractPartRenderer getRenderer(MUIElement uiElement, Object parent) {
		return curFactory.getRenderer(uiElement, parent);