[filemanager] Implementing undo delete functionality.

chrome/browser/resources/file_manager/js/metadata/metadata_cache.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.
 
 /**
  * MetadataCache is a map from url to an object containing properties.
  * Properties are divided by types, and all properties of one type are accessed
  * at once.
  * Some of the properties:
  * {
@@ skipping 278 matching lines @@
 };
 
 /**
  * Puts the metadata into cache
  * @param {string|Entry|Array.<string|Entry>} items The list of entries or
  *     file urls. May be just a single item.
  * @param {string} type The metadata type.
  * @param {Array.<Object>} values List of corresponding metadata values.
  */
 MetadataCache.prototype.set = function(items, type, values) {
-  if (!(items instanceof Array))
+  if (!(items instanceof Array)) {
     items = [items];
+    values = [values];
+  }
 
   this.startBatchUpdates();
   for (var index = 0; index < items.length; index++) {
     var url = this.itemToUrl_(items[index]);
     if (!(url in this.cache_)) {
       this.cache_[url] = this.createEmptyEntry_();
       this.totalCount_++;
     }
     this.cache_[url].properties[type] = values[index];
     this.notifyObservers_(url, type);
@@ skipping 628 matching lines @@
 
 /**
  * Handles the 'log' message from the worker.
  * @param {Array.<*>} arglist Log arguments.
  * @private
  */
 ContentProvider.prototype.onLog_ = function(arglist) {
   if (localStorage.logMetadata)  // Avoid log spam by default.
     console.log.apply(console, ['metadata:'].concat(arglist));
 };