Disable flaky MD Settings tests on Windows

chrome/test/data/webui/settings/cr_settings_browsertest.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.
 
 /** @fileoverview Runs the Polymer Settings tests. */
 
 /** @const {string} Path to source root. */
 var ROOT_PATH = '../../../../../';
 
 // Polymer BrowserTest fixture.
@@ skipping 750 matching lines @@
         assertEquals('a/b', settings.getQueryParameters().get('guid'));
         assertEquals('42', settings.getQueryParameters().get('foo'));
         done();
       });
       window.history.back();
     });
   });
   mocha.run();
 });
 
+// Times out on Windows Tests (dbg). See https://crbug.com/651296.
+GEN('#if defined(OS_WIN)');
+GEN('#define MAYBE_MainPage_All DISABLED_All');
+GEN('#else');
+GEN('#define MAYBE_MainPage_All All');
+GEN('#endif');
+
 /**
  * Test fixture for chrome/browser/resources/settings/settings_main/.
  * @constructor
  * @extends {CrSettingsBrowserTest}
 */
 function CrSettingsMainPageTest() {}
 
 CrSettingsMainPageTest.prototype = {
   __proto__: CrSettingsBrowserTest.prototype,
 
   /** @override */
   browsePreload: 'chrome://md-settings/settings_main/settings_main.html',
 
   /** @override */
   extraLibraries: CrSettingsBrowserTest.prototype.extraLibraries.concat([
     'settings_main_test.js',
   ]),
 };
 
-TEST_F('CrSettingsMainPageTest', 'All', function() {
+TEST_F('CrSettingsMainPageTest', 'MAYBE_MainPage_All', function() {
   settings_main_page.registerTests();
   mocha.run();
 });
 
 /**
  * @constructor
  * @extends {CrSettingsBrowserTest}
  */
 function CrControlledButtonTest() {}
 
@@ skipping 48 matching lines @@
     'test_privacy_page_browser_proxy.js',
     'metrics_reporting_tests.js',
   ]),
 };
 
 TEST_F('CrSettingsMetricsReportingTest', 'All', function() {
   mocha.run();
 });
 
 GEN('#endif');