Add tests for sync custom wallpaper feature

chrome/browser/resources/chromeos/wallpaper_manager/js/util.js

 // Copyright (c) 2013 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.
 
 var WallpaperUtil = {
   strings: null,  // Object that contains all the flags
   syncFs: null,   // syncFileSystem handler
   webkitFs: null  // webkitFileSystem handler
 };
 
@@ skipping 36 matching lines @@
 /**
  * Loads a wallpaper from sync file system and saves it and its thumbnail to
  *     local file system.
  * @param {string} wallpaperFileEntry File name of wallpaper image.
  */
 WallpaperUtil.storeWallpaperFromSyncFSToLocalFS = function(wallpaperFileEntry) {
   var filenName = wallpaperFileEntry.name;
   var storeDir = Constants.WallpaperDirNameEnum.ORIGINAL;
   if (filenName.indexOf(Constants.CustomWallpaperThumbnailSuffix) != -1)
     storeDir = Constants.WallpaperDirNameEnum.THUMBNAIL;
+  filenName = filenName.replace(Constants.CustomWallpaperThumbnailSuffix, '');
   wallpaperFileEntry.file(function(file) {
     var reader = new FileReader();
     reader.onloadend = function() {
       WallpaperUtil.storeWallpaperToLocalFS(filenName, reader.result, storeDir);
     };
     reader.readAsArrayBuffer(file);
   }, WallpaperUtil.onFileSystemError);
 };
 
 /**
@@ skipping 317 matching lines @@
  * Runs chrome.test.sendMessage in test environment. Does nothing if running
  * in production environment.
  *
  * @param {string} message Test message to send.
  */
 WallpaperUtil.testSendMessage = function(message) {
   var test = chrome.test || window.top.chrome.test;
   if (test)
     test.sendMessage(message);
 };