Files app: Handle chrome.runtime.lastError for chrome.storage API calls.

ui/file_manager/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.
 
 /**
  * Namespace for utility functions.
  */
 var util = {};
 
 /**
@@ skipping 369 matching lines @@
 
 /**
  * Save app launch data to the local storage.
  */
 util.saveAppState = function() {
   if (!window.appState)
     return;
   var items = {};
 
   items[window.appID] = JSON.stringify(window.appState);
-  chrome.storage.local.set(items);
+  chrome.storage.local.set(items, function() {
+    if (chrome.runtime.lastError)
+      console.error('Failed to save app state: ' +
+          chrome.runtime.lastError.message);
+  });
 };
 
 /**
  *  AppCache is a persistent timestamped key-value storage backed by
  *  HTML5 local storage.
  *
  *  It is not designed for frequent access. In order to avoid costly
  *  localStorage iteration all data is kept in a single localStorage item.
  *  There is no in-memory caching, so concurrent access is _almost_ safe.
  *
@@ skipping 660 matching lines @@
  * @return {!Promise} A promise which can be rejected by timeout.
  */
 util.timeoutPromise = function(promise, ms, opt_message) {
   return Promise.race([
     promise,
     util.delay(ms).then(function() {
       throw new Error(opt_message || 'Operation timed out.');
     })
   ]);
 };