|  | // Copyright 2015 The Chromium Authors. All rights reserved. | 
|  | // Use of this source code is governed by a BSD-style license that can be | 
|  | // found in the LICENSE file. | 
|  |  | 
|  | /** | 
|  | * @fileoverview Partial definitions for ECMAScript 7. To compile Files.app, some | 
|  | *     definitions are defined in this file. They should be removed once ES7 | 
|  | *     definitions are ready in closure compiler by default. | 
|  | * @externs | 
|  | */ | 
|  |  | 
|  | /** | 
|  | * @param {!Object} obj | 
|  | * @param {function(!Array<!Object>)} callback | 
|  | * @param {!Array<string>=} acceptList | 
|  | */ | 
|  | Object.observe = function(obj, callback, acceptList) {}; | 
|  |  | 
|  | /** | 
|  | * @param {!Object} obj | 
|  | * @param {function(!Array<!Object>)} callback | 
|  | */ | 
|  | Object.unobserve = function(obj, callback) {}; | 
|  |  | 
|  | /** | 
|  | * @param {!Array} arr | 
|  | * @param {function(!Array<!Object>)} callback | 
|  | */ | 
|  | Array.observe = function(arr, callback) {}; | 
|  |  | 
|  | /** | 
|  | * @param {!Array} arr | 
|  | * @param {function(!Array<!Object>)} callback | 
|  | */ | 
|  | Array.unobserve = function(arr, callback) {}; |