Disable flaky GuestModeOptionsUIBrowserTest

chrome/browser/ui/webui/options/chromeos/guest_mode_options_browsertest.js

 // Copyright 2016 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.
 
 GEN('#include "chrome/browser/ui/webui/options/chromeos/' +
     'guest_mode_options_browsertest.h"');
 
 /**
  * TestFixture for guest mode options WebUI testing.
  * @extends {testing.Test}
@@ skipping 23 matching lines @@
   },
 
   /** @param {!HTMLElement} el */
   expectHidden: function(el) {
     expectFalse(el.offsetHeight > 0 && el.offsetWidth > 0);
   },
 };
 
 /**
  * Test sections that should be hidden in guest mode.
+ * TODO(michaelpg): Debug flakiness: crbug.com/591154.
  */
-TEST_F('GuestModeOptionsUIBrowserTest', 'testSections', function() {
+TEST_F('GuestModeOptionsUIBrowserTest', 'DISABLED_testSections', function() {
   this.expectHidden($('startup-section'));
   this.expectHidden($('appearance-section'));
   this.expectHidden($('andorid-apps-section'));
   this.expectHidden($('sync-users-section'));
   this.expectHidden($('easy-unlock-section'));
   this.expectHidden($('reset-profile-settings-section'));
 });
 
 /**
  * Test controls that should be disabled in guest mode.
+ * TODO(michaelpg): Debug flakiness: crbug.com/591154.
  */
-TEST_F('GuestModeOptionsUIBrowserTest', 'testControls', function() {
+TEST_F('GuestModeOptionsUIBrowserTest', 'DISABLED_testControls', function() {
   // Appearance section.
   var setWallpaper = $('set-wallpaper');
   expectTrue(setWallpaper.disabled);
 
   // Passwords and autofill section.
   expectTrue($('autofill-enabled').disabled);
 
   // Date and time section.
   expectTrue($('timezone-value-select').disabled);
   expectFalse($('resolve-timezone-by-geolocation').disabled);
   expectFalse($('use-24hour-clock').disabled);
 
   // Privacy section.
   expectTrue(this.getControlForPref('search.suggest_enabled').disabled);
   expectTrue($('networkPredictionOptions').disabled);
 
   // Web content section.
   expectTrue($('defaultZoomFactor').disabled);
 
   // Downloads section.
   expectTrue(this.getControlForPref('gdata.disabled').disabled);
 
   // Content settings overlay.
   expectTrue(this.getControlForPref('settings.privacy.drm_enabled').disabled);
   expectTrue($('protected-content-exceptions').disabled);
 });