title: Requiring unknown module "498" error in ReactNative getting started example
body: <p>I'm trying to build and run an iOS simulator version of the getting started React Native project from the instructions at: </p>
  
  <p><a href="https://facebook.github.io/react-native/docs/getting-started.html" rel="noreferrer">https://facebook.github.io/react-native/docs/getting-started.html</a></p>
  
  <p>The app launches in the XCode simulator, displays it's window very briefly but then an exception occurs that opens a red screen with the message</p>
  
  <blockquote>
    <p>"Requiring unknown module "498".If you are sure the module is there,
    try restarting Metro Bundler. You may also want to run <code>yarn</code>, or <code>npm
    install</code> (depending on your environment).</p>
    
    <p>loadModuleImplementation require.js:176:29</p>
    
    <p> viewPropTypes.js:15:30</p>
    
    <p>loadModuleImplementation require.js:212:12</p>
    
    <p> View.js:20:22</p>
    
    <p>loadModuleImplementation require.js:212:12</p>
    
    <p> AppContainer.js:22:13"</p>
    
    <p>etc</p>
  </blockquote>
  
  <p>Line 15 of ViewPropTypes is</p>
  
  <pre><code>const PlatformViewPropTypes = require('PlatformViewPropTypes');
  </code></pre>
  
  <p>Line 20 of node_modules/react_native/Libraries/Components/Views/View.js is</p>
  
  <pre><code>const ViewPropTypes = require('ViewPropTypes');
  </code></pre>
  
  <p>Note: There is another, 15 line View.js files in the directory structure at node_modules/react_native/lib/ it's basically a stub containing </p>
  
  <pre><code>// This is a forwarding module to allow React to require React Native internals
  // as node dependency
  module.exports = require('View');
  </code></pre>
  
  <p>I'm on the latest of everything, MacOS High Sierra (10.13.4), XCode 9.3 with 9.3 command line tools installed. I've tried running yarn and npm install, and a fresh install. Obviously I have NPM and Watchman installed. Any ideas why the stock example won't run for me?</p>