[Files.app] Split the JavaScript files into subdirectories: common, background, and foreground

chrome/browser/resources/file_manager/common/js/path_util.js

 // Copyright (c) 2012 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.
 
 'use strict';
 
 /**
  * Type of a root directory.
  * @enum
  */
@@ skipping 347 matching lines @@
  * @param {string} filename Filename to be extracted.
  * @return {string} Extension of the given filename.
  */
 PathUtil.extractExtension = function(filename) {
   if (filename.indexOf('/') != -1)
     filename = filename.substr(filename.lastIndexOf('/') + 1);
   var extension = filename.lastIndexOf('.') != -1 ?
       filename.substr(filename.lastIndexOf('.') + 1) : '';
   return extension;
 };