Issue 4125 - [emscripten] Convert filter classes to C++

lib/filterClasses.js

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-2015 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 Definition of Filter class and its subclasses.
  */
 
+"use strict";
+
 let {FilterNotifier} = require("filterNotifier");
 let {Utils} = require("utils");
 
 /**
  * Abstract base class for filters
  *
  * @param {String} text   string representation of the filter
  * @constructor
  */
 function Filter(text)
@@ skipping 1029 matching lines @@
     // several times on Safari, due to WebKit bug 132872
     let prop = Object.getOwnPropertyDescriptor(this, "regexpString");
     if (prop)
       return prop.value;
 
     let regexp = Filter.toRegExp(this.regexpSource);
     Object.defineProperty(this, "regexpString", {value: regexp});
     return regexp;
   }
 };