| Index: ext/common.js | 
| =================================================================== | 
| --- a/ext/common.js | 
| +++ b/ext/common.js | 
| @@ -15,29 +15,33 @@ | 
| * along with Adblock Plus. If not, see <http://www.gnu.org/licenses/>. | 
| */ | 
| "use strict"; | 
| { | 
| window.ext = {}; | 
| - let EventTarget = ext._EventTarget = function() | 
| + ext._EventTarget = class | 
| { | 
| - this._listeners = new Set(); | 
| - }; | 
| - EventTarget.prototype = { | 
| + constructor() | 
| + { | 
| + this._listeners = new Set(); | 
| + } | 
| + | 
| addListener(listener) | 
| { | 
| this._listeners.add(listener); | 
| - }, | 
| + } | 
| + | 
| removeListener(listener) | 
| { | 
| this._listeners.delete(listener); | 
| - }, | 
| + } | 
| + | 
| _dispatch(...args) | 
| { | 
| let results = []; | 
| for (let listener of this._listeners) | 
| results.push(listener(...args)); | 
| return results; |