title: WKWebView not loading local files under iOS 8
body: <p>For previous iOS 8 betas, load a local web app (in Bundle) and it works fine for both <code>UIWebView</code> and <code>WKWebView</code>, and I even ported a web game using the new <code>WKWebView</code> API.</p>
  
  <pre><code>var url = NSURL(fileURLWithPath:NSBundle.mainBundle().pathForResource("car", ofType:"html"))
  
  webView = WKWebView(frame:view.frame)
  webView!.loadRequest(NSURLRequest(URL:url))
  
  view.addSubview(webView)
  </code></pre>
  
  <p>But in beta 4, I just got a blank white screen (<code>UIWebView</code> still work), looks like nothing is loaded or executed. I saw an error in the log:</p>
  
  <p>Could not create a sandbox extension for <code>/</code></p>
  
  <p>Any help to guide me to the right direction? Thanks!</p>