Issue 1241 - Element hiding exceptions broken in Firefox 34

lib/elemHideHitRegistration.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 108 matching lines @@
       try {
         listener.onStopRequest(this, context, Cr.NS_OK);
       } catch(e) {}
     }, this);
   },
 
   open: function()
   {
     let {Policy} = require("contentPolicy");
     let {ElemHide} = require("elemHide");
-    let data = "<bindings xmlns='http://www.mozilla.org/xbl'><binding id='dummy'/></bindings>";
+
+    // This dummy binding below won't have any effect on the element. For
+    // elements that should be hidden however we don't return any binding at
+    // all, this makes Gecko stop constructing the node - it cannot be shown.
+    let data = "<bindings xmlns='http://www.mozilla.org/xbl'><binding id='dummy' bindToUntrustedContent='true'/></bindings>";
     let filter = ElemHide.getFilterByKey(this.key);
     if (filter)
     {
       let wnd = Utils.getRequestWindow(this);
       if (wnd && wnd.document && !Policy.processNode(wnd, wnd.document, Policy.type.ELEMHIDE, filter))
         data = "<bindings xmlns='http://www.mozilla.org/xbl'/>";
     }
 
     let stream = Cc["@mozilla.org/io/string-input-stream;1"].createInstance(Ci.nsIStringInputStream);
     stream.setData(data, data.length);
@@ skipping 11 matching lines @@
   {
     throw Cr.NS_ERROR_NOT_IMPLEMENTED;
   },
   resume: function()
   {
     throw Cr.NS_ERROR_NOT_IMPLEMENTED;
   },
 
   QueryInterface: XPCOMUtils.generateQI([Ci.nsIChannel, Ci.nsIRequest])
 };