Issue 2401 - Integrate CSS property rule handling in Firefox

lib/whitelisting.js

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-2016 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
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with Adblock Plus.  If not, see <http://www.gnu.org/licenses/>.
  */
 
 /**
  * @fileOverview This is a dummy to provide a function needed by message
  * responder.
  */
 
 "use strict";
 
 let {Policy} = require("contentPolicy");
 let {RegExpFilter} = require("filterClasses");
 
+// NOTE: The function interface is supposed to be compatible with
+// checkWhitelisted in adblockpluschrome. That's why there is a typeMask
+// parameter here. However, this parameter is only used to decide whether
+// elemhide whitelisting should be considered, so only supported values for this
+// parameter are RegExpFilter.typeMap.DOCUMENT and
+// RegExpFilter.typeMap.DOCUMENT | RegExpFilter.typeMap.ELEMHIDE.
 exports.checkWhitelisted = function(page, frames, typeMask)
 {
   let match =
       Policy.isFrameWhitelisted(frames, typeMask & RegExpFilter.typeMap.ELEMHIDE);
   if (match)
   {
     let [frameIndex, matchType, docDomain, thirdParty, location, filter] = match;
     if (matchType == "DOCUMENT" || matchType == "ELEMHIDE")

[Thomas Greiner, 2016/03/30 18:02:06]

I noticed that this check doesn't exist in the original `checkWhitelisted()`
function. Depending on the intended purpose of this function (the description
and the implementation in adblockpluschrome are a bit divergent) we need to
either adapt the code here or in adblockpluschrome.

[Wladimir Palant, 2016/03/30 18:42:17]

This function doesn't really offer the same functionality as the one in
adblockpluschrome. This is fine however as there are really only two meaningful
values for typeMask parameter. I've added a comment on this.

IMHO the long-term solution would be moving part of content policy logic
(looping through frames in particular) into adblockpluscore so that the message
responder wouldn't rely on platform-specific stuff.

       return filter;
   }
 
   return null;
 };