Issue 1241 - Element hiding exceptions broken in Firefox 34

lib/elemHideHitRegistration.js

Index: lib/elemHideHitRegistration.js
===================================================================
--- a/lib/elemHideHitRegistration.js
+++ b/lib/elemHideHitRegistration.js
@@ -121,17 +121,21 @@ HitRegistrationChannel.prototype = {
       } 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'/>";
     }