Issue 1602 - Use ES6 generators instead of legacy generators

lib/filterStorage.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
@@ skipping 458 matching lines @@
           readFile(sourceFile, 0);
       }.bind(this);
 
       if (sourceFile)
         IO.statFile(sourceFile, callback);
       else
         callback(true);
     }
   },
 
-  _generateFilterData: function(subscriptions)
+  _generateFilterData: function*(subscriptions)
   {
     yield "# Adblock Plus preferences";
     yield "version=" + formatVersion;
 
     let saved = Object.create(null);
     let buf = [];
 
     // Save filter data
     for (let i = 0; i < subscriptions.length; i++)
     {
@@ skipping 373 matching lines @@
       Subscription.knownSubscriptions = origKnownSubscriptions;
     }
 
     // Allow events to be processed every now and then.
     // Note: IO.readFromFile() will deal with the potential reentrance here.
     this.linesProcessed++;
     if (this.linesProcessed % 1000 == 0)
       Utils.yield();
   }
 };