title: Why does v-if not get affected when the data is updated later?
body: <p>If I were to create an element such as that below:</p>
  
  <pre><code>&lt;div id="helloWorldDiv" v-if="visible"&gt;
      Hello World
  &lt;/div&gt;
  </code></pre>
  
  <p>and then create a Vue instance for it:</p>
  
  <pre><code>var helloWorld = new Vue({
    el: "#helloWorldDiv",
    data: {
      visible: false
    }
  });
  </code></pre>
  
  <p>I would expect that the line '<code>helloWorld.visible = true;</code>' would show the element, but it has not effect. Can anyone explain why this doesn't work?</p>
  
  <p><a href="https://jsfiddle.net/4yegjhv8/1/" rel="nofollow">JSFiddle</a></p>