Issue 6868 - Enable capturing of surrounding wildcards for rewrite filters

lib/filterClasses.js

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-present 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 630 matching lines @@
    * for delayed creation of the regexp property
    * @type {string}
    */
   regexpSource: null,
   /**
    * Regular expression to be used when testing against this filter
    * @type {RegExp}
    */
   get regexp()
   {
-    let source = filterToRegExp(this.regexpSource, this.rewrite == null);
+    let source = filterToRegExp(this.regexpSource, this.rewrite != null);
     let regexp = new RegExp(source, this.matchCase ? "" : "i");
     Object.defineProperty(this, "regexp", {value: regexp});
     this.regexpSource = null;
     return regexp;
   },
   /**
    * Content types the filter applies to, combination of values from
    * RegExpFilter.typeMap
    * @type {number}
    */
@@ skipping 515 matching lines @@
 
   /**
    * Script that should be executed
    * @type {string}
    */
   get script()
   {
     return this.body;
   }
 });