title: React doesn't prevent form submit in IE 11
body: <p>Facing one problem with my component that I can not solve using React 15 . Everything works as expected, except in IE 11. </p>
  
  <p>Basically looks like IE 11 is ignoring the event.preventDefault() function  (and all of the commented functions in the code below, tried with all of them) and submits the data. The page gets reloaded and the query parameters are in the url. I would like to prevent the reloading of the page and execute just the logic in the handleSubmit function.</p>
  
  <p>The form in the render function:</p>
  
  <pre><code>&lt;form onSubmit={this.handleSubmit}&gt;
     &lt;input ref="email" type="email" name="username" required&gt;&lt;/input&gt;
     &lt;input ref="pass" type="password" name="pass"required&gt;&lt;/input&gt;
     &lt;input type="submit" name="login" value="Login" /&gt;
  &lt;/form&gt;
  </code></pre>
  
  <p>and this is the hanleSubmit function:</p>
  
  <pre><code>handleSubmit: function (event) {
  
     event.preventDefault();
     //event.returnValue = false;
     //event.stopPropagation();
     //event.nativeEvent.preventDefault(); 
  
     var email = this.refs.email.value;
     var pass = this.refs.pass.value;
  
     //return false;
  },
  </code></pre>