Fix typo in a Files app tests.

ui/file_manager/integration_tests/testing_provider/background.js

 // Copyright 2015 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';
 
 var dialogSettings = {};
 
 function mountFileSystem(onSuccess, onError) {
   chrome.fileSystemProvider.getAll(function(mounted) {
@@ skipping 31 matching lines @@
           function() {
             if (chrome.runtime.lastError)
               onError(chrome.runtime.lastError.message);
             else
               onSuccess();
           });
     });
 
 chrome.fileSystemProvider.onGetActionsRequested.addListener(
     function(options, onSuccess, onError) {
-      onSucces([]);
+      onSuccess([]);
     });
 
 // If the manifest for device or file source is used, then mount a fake file
 // system on install.
 if (chrome.runtime.getManifest().name === "Testing Provider Device" ||
     chrome.runtime.getManifest().name === "Testing Provider File") {
   chrome.runtime.onInstalled.addListener(mountFileSystem);
 }