[sheriff] Disable LoginOfflineManagedTest.LoginAllowlistedUser

Bug: 1240601
Change-Id: Idcd6b3b5b2637c858c80d73b7690313880167ef9
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3114345
Owners-Override: Xida Chen <xidachen@chromium.org>
Auto-Submit: Xida Chen <xidachen@chromium.org>
Reviewed-by: Ella Ge <eirage@chromium.org>
Commit-Queue: Xida Chen <xidachen@chromium.org>
Cr-Commit-Position: refs/heads/main@{#914380}

chrome/browser/ash/login/login_browsertest.cc

@@ -387,7 +387,13 @@ IN_PROC_BROWSER_TEST_F(LoginOfflineManagedTest, BackButtonTest) {
   EXPECT_TRUE(ash::LoginScreenTestApi::IsOobeDialogVisible());
 }
 
-IN_PROC_BROWSER_TEST_F(LoginOfflineManagedTest, LoginAllowlistedUser) {
+// crbug.com/1240601: test is flaky on chromeos.
+#if defined(OS_CHROMEOS)
+#define MAYBE_LoginAllowlistedUser DISABLED_LoginAllowlistedUser
+#else
+#define MAYBE_LoginAllowlistedUser LoginAllowlistedUser
+#endif
+IN_PROC_BROWSER_TEST_F(LoginOfflineManagedTest, MAYBE_LoginAllowlistedUser) {
   std::string domain = gaia::ExtractDomainName(managed_user_id_.GetUserEmail());
   ConfigurePolicy(domain);
   SetDeviceAllowNewUsersPolicy(false);