message: fix(action-bar): ignore InvisibleNodes when adding title
  fixes
diff: @@ -5,6 +5,7 @@ import { View } from "tns-core-modules/ui/core/view";
  import { isBlank } from "../lang-facade";
  import {
  + InvisibleNode,
  NgView,
  ViewClassMeta,
  registerElement,
  @@ -16,7 +17,9 @@ const actionBarMeta: ViewClassMeta = {
  const bar = <ActionBar>(<any>parent);
  const childView = <any>child;
  - if (child instanceof NavigationButton) {
  + if (child instanceof InvisibleNode) {
  + return;
  + } else if (child instanceof NavigationButton) {
  bar.navigationButton = childView;
  childView.parent = bar;
  } else if (child instanceof ActionItem) {
  @@ -30,7 +33,9 @@ const actionBarMeta: ViewClassMeta = {
  const bar = <ActionBar>(<any>parent);
  const childView = <any>child;
  - if (child instanceof NavigationButton) {
  + if (child instanceof InvisibleNode) {
  + return;
  + } else if (child instanceof NavigationButton) {
  if (bar.navigationButton === childView) {
  bar.navigationButton = null;
  }
  