title: NavigationStateUtils not pushing (using NavigationExperimental)
body: <p>Here's my AppState class:</p>
  
  <pre><code>export default class AppState {
      constructor() {
          this.navigationState = {
              index: 0,
              routes: [{ key: "InitialView" }]
          };
      }
      updateNavigationState(type, route = null) {
          switch (type) {
              case NavigationStateUpdateType.Push:
                  console.log(this.navigationState.routes.length);
                  console.log(this.navigationState.routes[0].key);
                  if (route !== null) {
                      console.log("Route: " + route);
                      this.navigationState = NavigationStateUtils.push(this.navigationState, { key: route });
                  }
              case NavigationStateUpdateType.Pop:
                  this.navigationState = NavigationStateUtils.pop(this.navigationState);
          }
      }
  }
  </code></pre>
  
  <p>Now if I do this inside <code>InitialView</code>:</p>
  
  <pre><code>this.props.appState.updateNavigationState(NavigationStateUpdateType.Push, "InitialView1");
  </code></pre>
  
  <p>Nothing happens. It seems like <code>NavigationStateUtil.push</code>doesn't work. Here's what the Console looks like:</p>
  
  <pre><code>AppState.js:18 1
  AppState.js:19 InitialView
  AppState.js:21 Route: InitialView1
  AppState.js:18 1
  AppState.js:19 InitialView
  AppState.js:21 Route: InitialView1
  AppState.js:18 1
  AppState.js:19 InitialView
  AppState.js:21 Route: InitialView1
  </code></pre>
  
  <p>Why isn't <code>routes</code> being updated? Or am I doing something wrong?</p>
  
  <p>EDIT</p>
  
  <p>My <code>GlobalNavigation</code> component (as asked):</p>
  
  <pre><code>const { CardStack: NavigationCardStack } = NavigationExperimental;
  let GlobalNavigation = class GlobalNavigation extends Component {
      render() {
          return (React.createElement(NavigationCardStack, {renderScene: this._renderScene.bind(this), navigationState: this.props.appState.navigationState}));
      }
      _renderScene() {
          return (React.createElement(InitialView, {appState: this.props.appState}));
      }
  };
  </code></pre>
  
  <p>By the way: all this code is generated by TypeSript.</p>