[Sheriff] Disable ChromeVoxNavigateAndSelect on CrOS - flaky.

chrome/browser/chromeos/accessibility/spoken_feedback_browsertest.cc

 // 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.
 
 #include <queue>
 
 #include "ash/accelerators/accelerator_controller.h"
 #include "ash/accelerators/accelerator_table.h"
 #include "ash/accessibility_types.h"
 #include "ash/shell.h"
@@ skipping 514 matching lines @@
   // Press Search+/ to enter ChromeVox's "find in page".
   SendKeyPressWithSearch(ui::VKEY_OEM_2);
 
   while (true) {
     std::string utterance = speech_monitor_.GetNextUtterance();
     if (utterance == "Find in page.")
       break;
   }
 }
 
-#if defined(MEMORY_SANITIZER)
+#if defined(MEMORY_SANITIZER) || defined(OS_CHROMEOS)
 // Fails under MemorySanitizer: http://crbug.com/472125
+// TODO(crbug.com/721475): Flaky on CrOS.
 #define MAYBE_ChromeVoxNavigateAndSelect DISABLED_ChromeVoxNavigateAndSelect
 #else
 #define MAYBE_ChromeVoxNavigateAndSelect ChromeVoxNavigateAndSelect
 #endif
 IN_PROC_BROWSER_TEST_P(SpokenFeedbackTest, MAYBE_ChromeVoxNavigateAndSelect) {
   EnableChromeVox();
 
   ui_test_utils::NavigateToURL(browser(),
                                GURL("data:text/html;charset=utf-8,"
                                     "<h1>Title</h1>"
@@ skipping 202 matching lines @@
   ASSERT_TRUE(ui_test_utils::SendKeyPressToWindowSync(
       window, ui::VKEY_TAB, false, true /*shift*/, false, false));
   while (speech_monitor_.GetNextUtterance() != "Select your language:") {
   }
   EXPECT_EQ("English ( United States)", speech_monitor_.GetNextUtterance());
   EXPECT_TRUE(base::MatchPattern(speech_monitor_.GetNextUtterance(),
                                  "Combo box * of *"));
 }
 
 }  // namespace chromeos