Issue 1522 - Use classList attribute instead dealing with className

include.postload.js

 /*
  * This file is part of Adblock Plus <http://adblockplus.org/>,
  * Copyright (C) 2006-2014 Eyeo GmbH
  *
  * Adblock Plus is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 3 as
  * published by the Free Software Foundation.
  *
  * Adblock Plus is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 350 matching lines @@
 // When the user clicks, the currentElement is the one we want.
 // We should have ABP rules ready for when the
 // popup asks for them.
 function clickHide_mouseClick(e)
 {
   if (!currentElement || !clickHide_activated)
     return;
 
   var elt = currentElement;
   var url = null;
-  if (currentElement.className && currentElement.className == "__adblockplus__overlay")
+  if (currentElement.classList.contains("__adblockplus__overlay"))
   {
     elt = currentElement.prisoner;
     url = currentElement.prisonerURL;
   }
   else if (elt.src)
     url = elt.src;
 
   // Construct filters. The popup will retrieve these.
   // Only one ID
   var elementId = elt.id ? elt.id.split(' ').join('') : null;
-  // Can have multiple classes, and there might be extraneous whitespace
-  var elementClasses = null;
-  if (elt.className)
-    elementClasses = elt.className.replace(/\s+/g, ' ').replace(/^\s+|\s+$/g, '').split(' ');
 
   clickHideFilters = new Array();
   selectorList = new Array();
 
   var addSelector = function(selector)
   {
     clickHideFilters.push(document.domain + "##" + selector);
     selectorList.push(selector);
   };
 
   if (elementId)
     addSelector("#" + elementId);
 
-  if (elementClasses && elementClasses.length > 0)
+  if (elt.classList.length > 0)
   {
     var selector = "";
 
     for (var i = 0; i < elt.classList.length; i++)
       selector += "." + elt.classList[i].replace(/([^\w-])/g, "\\$1");
 
     addSelector(selector);
   }
 
   if (url)
@@ skipping 253 matching lines @@
         break;
       default:
         sendResponse({});
         break;
     }
   });
 
   if (window == window.top)
     ext.backgroundPage.sendMessage({type: "report-html-page"});
 }