Files.app: Show error messages for the case the source file is not exists.

chrome/browser/resources/file_manager/common/js/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';
 
 /**
  * Namespace for utility functions.
  */
 var util = {};
@@ skipping 1131 matching lines @@
   return entries.map(function(entry) {
      return entry.toURL();
   });
 };
 
 /**
  * Converts array of URLs to an array of corresponding Entries.
  *
  * @param {Array.<string>} urls Input array of URLs.
  * @param {function(Array.<Entry>)} callback Completion callback with array of
  *     Entries.

[yoshiki, 2014/02/14 10:24:11]

Please mention that the both errorCallback and callback are called in error.

Or can't we combine these 2 callbacks?

[hirono, 2014/02/14 10:42:37]

Let me combine the callbacks!

+ * @param {function(Array.<Entry>)} opt_errorCallback Error callback with array
+ *     of URLs failed to be resolved.
  */
-util.URLsToEntries = function(urls, callback) {
+util.URLsToEntries = function(urls, callback, opt_errorCallback) {
   var result = [];
+  var failureUrl = [];
   AsyncUtil.forEach(
       urls,
       function(forEachCallback, url) {
         webkitResolveLocalFileSystemURL(url, function(entry) {
           result.push(entry);
           forEachCallback();
         }, function() {
           // Not an error. Possibly, the file is not accessible anymore.
           console.warn('Failed to resolve the file with url: ' + url + '.');
+          failureUrl.push(url);
           forEachCallback();
         });
       },
       function() {
         callback(result);
+        if (opt_errorCallback)
+          opt_errorCallback(failureUrl);
       });
 };
 
 /**
  * Returns whether the window is teleported or not.
  * @param {DOMWindow} window Window.
  * @return {Promise.<boolean>} Whether the window is teleported or not.
  */
 util.isTeleported = function(window) {
   return new Promise(function(onFulfilled) {
@@ skipping 60 matching lines @@
  * @enum {string}
  * @const
  */
 util.VolumeType = Object.freeze({
   DRIVE: 'drive',
   DOWNLOADS: 'downloads',
   REMOVABLE: 'removable',
   ARCHIVE: 'archive',
   CLOUD_DEVICE: 'cloud_device'
 });