title: How to run code before Chrome app has been uninstalled
body: <p>From the <a href="http://developer.chrome.com/extensions/runtime#event-onInstalled" rel="nofollow">chrome docs</a> I can see that one can subscribe to an 'installed' and 'updated' events using the following code:</p>
  
  <pre><code>chrome.runtime.onInstalled.addListener function(){
      // do something when the app is installed
  }
  </code></pre>
  
  <p>My question is: Is there some when to subscribe to the event where the user decides to uninstall the app? i.e. something like:</p>
  
  <pre><code>chrome.runtime.onUninstall.addListener function(){
      // do something when the app is installed
  }
  </code></pre>