title: WKWebview fails to load css styles when html code contains unicode chars
body: <p>I found a strange behavior in the WKWebView: </p>
  
  <p>I use to load the HTML text from a file in the bundle, and I also use a css file, also in the bundle.</p>
  
  <p>While this approach always works with UIWebView, with the new WKWebView class it only works if the html text does not contain unicode chars like "–" (U+2013).</p>
  
  <p>I've created a test project for that, that demonstrates the issue, attached a screenshot from there.</p>
  
  <p>As it's visible in the screenshot (the webView2, in the middle of the device) when the html text contains the "–" sign, the displayed text is not styled as it should (webView1, on the top). If we load the same html from a remote server, using the loadRequest call, it works indeed (webView3, on the bottom).
  Using the UIWebview objects, everything works fine instead.</p>
  
  <p>The HTML used is this one:</p>
  
  <p>story.html:</p>
  
  <pre><code>&lt;html&gt;&lt;meta charset="UTF-8"&gt;&lt;link rel="stylesheet" type="text/css" href="Styles.css" /&gt;&lt;body&gt;&lt;div&gt;123123&lt;/div&gt;&lt;/body&gt;&lt;html&gt;
  </code></pre>
  
  <p>story_failing.html</p>
  
  <pre><code>&lt;html&gt;&lt;meta charset="UTF-8"&gt;&lt;link rel="stylesheet" type="text/css" href="Styles.css" /&gt;&lt;body&gt;123–123&lt;/body&gt;&lt;html&gt;
  </code></pre>
  
  <p>Styles.css</p>
  
  <pre><code>body {
  
  font-size:80px;
  color: #FF0000;
  </code></pre>
  
  <p>}</p>
  
  <p><img src="https://i.stack.imgur.com/gr4dl.jpg" alt="enter image description here"></p>