DNS probes: several tweaks to error page updating

chrome/renderer/resources/neterror.js

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 function toggleHelpBox() {
   var helpBoxOuter = document.getElementById('help-box-outer');
   helpBoxOuter.classList.toggle('hidden');
   var moreLessButton = document.getElementById('more-less-button');
   if (helpBoxOuter.classList.contains('hidden')) {
     moreLessButton.innerText = moreLessButton.moreText;
   } else {
     moreLessButton.innerText = moreLessButton.lessText;
   }
 }
 
 function diagnoseErrors() {
   var extension_id = "idddmepepmjcgiedknnmlbadcokidhoa";
   var diagnose_frame = document.getElementById('diagnose-frame');
   diagnose_frame.innerHTML =
       '<iframe src="chrome-extension://' + extension_id +
       '/index.html"></iframe>';
 }
 
 // Subframes use a different layout but the same html file.  This is to make it
 // easier to support platforms that load the error page via different
 // mechanisms (Currently just iOS).
 if (window.top.location != window.location)
   document.documentElement.setAttribute('subframe', '');
 
+// Re-renders the error page using |strings| as the dictionary of values.
+// Used by NetErrorTabHelper to update DNS error pages with probe results.
 function updateForDnsProbe(strings) {
+  i18nTemplate.process(document, strings);
   var context = new JsEvalContext(strings);
-  jstProcess(context, document.getElementById('help-box-outer'));
-  jstProcess(context, document.getElementById('details'));
+  jstProcess(context, document.getElementById('t'));
+}
+
+// Given the classList property of an element, adds an icon class to the list
+// and removes the previously-
+function updateIconClass(classList, newClass) {
+  var oldClass;
+
+  if (classList.hasOwnProperty('last_icon_class')) {
+    oldClass = classList['last_icon_class']
+    if (oldClass == newClass)
+      return;
+  }
+
+  classList.add(newClass);
+  if (oldClass !== undefined)
+    classList.remove(oldClass);
+
+  classList['last_icon_class'] = newClass;
 }
 
 <if expr="is_macosx or is_ios or is_linux or is_android">
 // Re-orders buttons. Used on Mac, Linux, and Android, where reload should go
 // on the right.
 function swapButtonOrder() {
   reloadButton = document.getElementById('reload-button');
   moreLessButton = document.getElementById('more-less-button');
   reloadButton.parentNode.insertBefore(moreLessButton, reloadButton);
 }
 document.addEventListener("DOMContentLoaded", swapButtonOrder);
 </if>