Gallery.app: make edit button toggleable.

ui/file_manager/integration_tests/gallery/photo_editor.js

 // Copyright 2014 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';
 
 /**
  * Prepares the photo editor.
  *
  * @param {string} testVolumeName Test volume name passed to the addEntries
@@ skipping 12 matching lines @@
 
     // Show the slide image.
     var slideImagePromise = gallery.waitForSlideImage(
         appId,
         800,
         600,
         'My Desktop Background');
 
     // Lauch the photo editor.
     var photoEditorPromise = slideImagePromise.then(function() {
-      return gallery.waitAndClickElement(appId, '.button.edit');
+      return gallery.waitAndClickElement(appId, 'button.edit');
     });
 
     return photoEditorPromise.then(function() {
       return args;
     });
   });
 }
 
 /**
  * Tests to rotate an image.
@@ skipping 176 matching lines @@
   return exposureImage('local', 'downloads');
 };
 
 /**
  * The exposureImage test for Google Drive.
  * @return {Promise} Promise to be fulfilled with on success.
  */
 testcase.exposureImageOnDrive = function() {
   return exposureImage('drive', 'drive');
 };