Issue 4962 - Fix the tests.- Fix syntax in chrome/content/elemHideEmulation.js to use ES5Regress…

chrome/content/elemHideEmulation.js

Index: chrome/content/elemHideEmulation.js
===================================================================
--- a/chrome/content/elemHideEmulation.js
+++ b/chrome/content/elemHideEmulation.js
@@ -78,38 +78,37 @@ ElemHideEmulation.prototype = {
 
   findSelectors: function(stylesheet, selectors, filters)
   {
     // Explicitly ignore third-party stylesheets to ensure consistent behavior
     // between Firefox and Chrome.
     if (!this.isSameOrigin(stylesheet))
       return;
 
-    let rules = stylesheet.cssRules;
+    var rules = stylesheet.cssRules;
     if (!rules)
       return;
 
-    for (let rule of rules)
+    for (var i = 0; i < rules.length; i++)
     {
+      var rule = rules[i];
       if (rule.type != rule.STYLE_RULE)
         continue;
 
-      let style = this.stringifyStyle(rule.style);
-      for (let pattern of this.patterns)
-      {
+      var style = this.stringifyStyle(rule.style);
+      this.patterns.forEach(function(pattern) {
         if (pattern.regexp.test(style))
         {
-          let subSelectors = splitSelector(rule.selectorText);
-          for (let subSelector of subSelectors)
-          {
+          var subSelectors = splitSelector(rule.selectorText);
+          subSelectors.forEach(function(subSelector) {
             selectors.push(pattern.prefix + subSelector + pattern.suffix);
             filters.push(pattern.text);
-          }
+          });
         }
-      }
+      });
     }
   },
 
   addSelectors: function(stylesheets)
   {
     var selectors = [];
     var filters = [];
     for (var i = 0; i < stylesheets.length; i++)