[Sheriff] Disable UpdateIncognitoEnableDisable on CrOS - flaky.

chrome/browser/sync/test/integration/two_client_app_list_sync_test.cc

Index: chrome/browser/sync/test/integration/two_client_app_list_sync_test.cc
diff --git a/chrome/browser/sync/test/integration/two_client_app_list_sync_test.cc b/chrome/browser/sync/test/integration/two_client_app_list_sync_test.cc
index 2a49412a51316d121daac3b121dfdcd4ce6ce4e1..a55eaa5c418205692cd825967515842e10b7bf56 100644
--- a/chrome/browser/sync/test/integration/two_client_app_list_sync_test.cc
+++ b/chrome/browser/sync/test/integration/two_client_app_list_sync_test.cc
@@ -297,7 +297,14 @@ IN_PROC_BROWSER_TEST_F(TwoClientAppListSyncTest, UpdateEnableDisableApp) {
   ASSERT_TRUE(IsAppEnabled(GetProfile(1), 0));
 }
 
-IN_PROC_BROWSER_TEST_F(TwoClientAppListSyncTest, UpdateIncognitoEnableDisable) {
+// TODO(crbug.com/721391) Flaky on CrOS.
+#if defined(OS_CHROMEOS)
+#define MAYBE_UpdateIncognitoEnableDisable DISABLED_UpdateIncognitoEnableDisable
+#else
+#define MAYBE_UpdateIncognitoEnableDisable UpdateIncognitoEnableDisable
+#endif
+IN_PROC_BROWSER_TEST_F(TwoClientAppListSyncTest,
+                       MAYBE_UpdateIncognitoEnableDisable) {
   ASSERT_TRUE(SetupSync());
   ASSERT_TRUE(AllProfilesHaveSameAppList());