[oobe]: Add flag --oobe-skip-to-login

This flag skips to the user login screen.

BUG=753870
TEST=manual

Change-Id: I3682b825d8177b8676718f421335f4af1d940937
Reviewed-on: https://chromium-review.googlesource.com/850582
Commit-Queue: Achuith Bhandarkar <achuith@chromium.org>
Reviewed-by: Alexander Alekseev <alemate@chromium.org>
Cr-Commit-Position: refs/heads/master@{#527116}

chrome/browser/chromeos/login/wizard_controller.cc

@@ -370,6 +370,11 @@ void WizardController::Init(OobeScreen first_screen) {
   if (!IsMachineHWIDCorrect() && !StartupUtils::IsDeviceRegistered() &&
       first_screen_ == OobeScreen::SCREEN_UNKNOWN)
     ShowWrongHWIDScreen();
+
+  if (is_out_of_box_ && base::CommandLine::ForCurrentProcess()->HasSwitch(
+                            chromeos::switches::kOobeSkipToLogin)) {
+    SkipToLoginForTesting(LoginScreenContext());
+  }
 }
 
 ErrorScreen* WizardController::GetErrorScreen() {

chromeos/chromeos_switches.cc

@@ -459,6 +459,9 @@ const char kOobeGuestSession[] = "oobe-guest-session";
 // Skips all other OOBE pages after user login.
 const char kOobeSkipPostLogin[] = "oobe-skip-postlogin";
 
+// Skip to login screen.
+const char kOobeSkipToLogin[] = "oobe-skip-to-login";
+
 // Interval at which we check for total time on OOBE.
 const char kOobeTimerInterval[] = "oobe-timer-interval";
 

chromeos/chromeos_switches.h

@@ -137,6 +137,7 @@ CHROMEOS_EXPORT extern const char kOobeBootstrappingMaster[];
 CHROMEOS_EXPORT extern const char kOobeForceShowScreen[];
 CHROMEOS_EXPORT extern const char kOobeGuestSession[];
 CHROMEOS_EXPORT extern const char kOobeSkipPostLogin[];
+CHROMEOS_EXPORT extern const char kOobeSkipToLogin[];
 CHROMEOS_EXPORT extern const char kOobeTimerInterval[];
 CHROMEOS_EXPORT extern const char kShillStub[];
 CHROMEOS_EXPORT extern const char kShowLoginDevOverlay[];