Issue 427 - Desugar arrow functions to normal or bound functions

autotest/test_abprewrite.js.expected

 /*
  * This file is part of Adblock Plus <http://adblockplus.org/>,
  * Copyright (C) 2006-2014 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 102 matching lines @@
 }
 var a = function()
 {
   var _generatorResult10 = [];
   for (var i = 0; i < 10; i++)
   {
     _generatorResult10.push(i);
   }
   return _generatorResult10;
 };
+var x = function(y)
+{
+  return y + 1;
+};
+x = function(y)
+{
+  return y + 1;
+};
+x = function(a, b)
+{
+  return this[a] + b;
+}.bind(this);
+x = function(a, b)
+{
+  return function()
+  {
+    return 1;
+  };
+}.bind(this);