[Files.app] Remove OK and Cancel buttons in task picker dialog

chrome/browser/resources/file_manager/foreground/js/file_manager_commands.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';
 
 /**
  * TODO(dzvorygin): Here we use this hack, since 'hidden' is standard
  * attribute and we can't use it's setter as usual.
  * @param {boolean} value New value of hidden property.
@@ skipping 572 matching lines @@
 /**
  * Displays open with dialog for current selection.
  * @type {Command}
  */
 CommandHandler.COMMANDS_['open-with'] = {
   execute: function(event, fileManager) {
     var tasks = fileManager.getSelection().tasks;
     if (tasks) {
       tasks.showTaskPicker(fileManager.defaultTaskPicker,
           str('OPEN_WITH_BUTTON_LABEL'),
-          null,
+          '',
           function(task) {
             tasks.execute(task.taskId);
           });
     }
   },
   canExecute: function(event, fileManager) {
     var tasks = fileManager.getSelection().tasks;
     event.canExecute = tasks && tasks.size() > 1;
   }
 };
@@ skipping 243 matching lines @@
 /**
  * Reset the zoom factor.
  * @type {Command}
  */
 CommandHandler.COMMANDS_['zoom-reset'] = {
   execute: function(event, fileManager) {
     chrome.fileBrowserPrivate.zoom('reset');
   },
   canExecute: CommandUtil.canExecuteAlways
 };