title: webpack: bundle is now INVALID. webpack: bundle is now VALID
body: <p>I have just started working on React.js recently. I am following some tutorials and testing some examples from it. But, as I reached an example of props, it doesn't run. I can't understand the problem. Following is the output on my CMD:</p>
  
  <pre><code>    webpack: bundle is now INVALID.
      Hash: b3302b07f8d42d8d5049
      Version: webpack 1.13.1
      Time: 297ms
      chunk    {0} index.js (main) 906 kB
      [76] ./main.js 582 bytes {0} [built]
      + 247 hidden modules
      webpack: bundle is now VALID.
  </code></pre>
  
  <p>Here is Props.jsx:</p>
  
  <pre><code>import React from 'react';
  
  class App extends React.Component {
     render() {
        return (
           &lt;div&gt;
              &lt;h1&gt;{this.props.headerProp}&lt;/h1&gt;
              &lt;h2&gt;{this.props.contentProp}&lt;/h2&gt;
           &lt;/div&gt;
        );
     }
  }
  
  App.defaultProps = {
     headerProp: "Header from props...",
     contentProp: contentProp = "Content from props..."
  }
  
  export default App;
  </code></pre>
  
  <p>And here is main.js:</p>
  
  <pre><code>import React from 'react';
  import ReactDOM from 'react-dom';
  import App from './Props.jsx';
  
  ReactDOM.render(&lt;App /&gt;, document.getElementById('app'));
  
  export default App;
  </code></pre>