oobe: fix fake enterprise enrollment login

Allow fake login to continue without an OAuth cookie to fix the
fake enterprise enrollment.

Bug: chromium:1140422
Test: tast run <ip> policy.SystemTimezone
Change-Id: I75985607421c370c610336b1afbcf5b7c708da89
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2487268
Commit-Queue: Victor-Gabriel Savu <vsavu@google.com>
Reviewed-by: Roman Sorokin [CET] <rsorokin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#818960}

chrome/browser/ui/webui/chromeos/login/enrollment_screen_handler.cc

@@ -735,6 +735,7 @@ void EnrollmentScreenHandler::HandleToggleFakeEnrollment() {
   VLOG(1) << "HandleToggleFakeEnrollment";
   policy::PolicyOAuth2TokenFetcher::UseFakeTokensForTesting();
   WizardController::SkipEnrollmentPromptsForTesting();
+  use_fake_login_for_testing_ = true;
 }
 
 void EnrollmentScreenHandler::HandleClose(const std::string& reason) {
@@ -825,8 +826,10 @@ void EnrollmentScreenHandler::OnGetCookiesForCompleteLogin(
     }
   }
 
-  if (auth_code.empty()) {
+  // Allow testing to continue without a oauth cookie.
+  if (auth_code.empty() && !use_fake_login_for_testing_) {
     // Will try again from oauth_code_waiter callback.
+    VLOG(1) << "OAuth cookie empty, still waiting";
     return;
   }
 
@@ -836,6 +839,7 @@ void EnrollmentScreenHandler::OnGetCookiesForCompleteLogin(
 }
 
 void EnrollmentScreenHandler::OnCookieWaitTimeout() {
+  LOG(ERROR) << "Timeout waiting for OAuth cookie";
   oauth_code_waiter_.reset();
   ShowError(IDS_LOGIN_FATAL_ERROR_NO_AUTH_TOKEN, true);
 }

chrome/browser/ui/webui/chromeos/login/enrollment_screen_handler.h

@@ -194,6 +194,8 @@ class EnrollmentScreenHandler
 
   std::unique_ptr<CookieWaiter> oauth_code_waiter_;
 
+  bool use_fake_login_for_testing_ = false;
+
   base::WeakPtrFactory<EnrollmentScreenHandler> weak_ptr_factory_{this};
 
   DISALLOW_COPY_AND_ASSIGN(EnrollmentScreenHandler);