1) Add initialization error page; 2) Add connection error page.

chrome/browser/chromeos/login/screens/host_pairing_screen.cc

Index: chrome/browser/chromeos/login/screens/host_pairing_screen.cc
diff --git a/chrome/browser/chromeos/login/screens/host_pairing_screen.cc b/chrome/browser/chromeos/login/screens/host_pairing_screen.cc
index 021ab6f5dbbf6028c0e01ea3f11b8cb4361d2c91..0c84bb6646dd6f5baa9eb38ac4ebd0f8ee6393e9 100644
--- a/chrome/browser/chromeos/login/screens/host_pairing_screen.cc
+++ b/chrome/browser/chromeos/login/screens/host_pairing_screen.cc
@@ -5,11 +5,13 @@
 #include "chrome/browser/chromeos/login/screens/host_pairing_screen.h"
 
 #include "base/command_line.h"
+#include "base/prefs/pref_service.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/chromeos/login/startup_utils.h"
 #include "chrome/browser/chromeos/login/wizard_controller.h"
 #include "chrome/browser/chromeos/policy/browser_policy_connector_chromeos.h"
 #include "chrome/browser/chromeos/policy/enrollment_status_chromeos.h"
+#include "chrome/common/pref_names.h"
 #include "components/pairing/host_pairing_controller.h"
 
 namespace chromeos {
@@ -17,6 +19,18 @@ namespace chromeos {
 using namespace host_pairing;
 using namespace pairing_chromeos;
 
+namespace {
+
+// Clear Enrollment related local state after a successful enrollment or when
+// an error occurs.
+void ClearEnrollmentLocalState() {
+  g_browser_process->local_state()->ClearPref(
+      prefs::kDeviceEnrollmentAutoStart);
+  g_browser_process->local_state()->ClearPref(prefs::kDeviceEnrollmentCanExit);
+}
+
+}  // namespace
+
 HostPairingScreen::HostPairingScreen(
     BaseScreenDelegate* base_screen_delegate,
     Delegate* delegate,
@@ -68,6 +82,11 @@ std::string HostPairingScreen::GetName() const {
 void HostPairingScreen::PairingStageChanged(Stage new_stage) {
   std::string desired_page;
   switch (new_stage) {
+    case HostPairingController::STAGE_INITIALIZATION_ERROR: {
+      desired_page = kPageIntializationError;
+      ClearEnrollmentLocalState();
+      break;
+    }
     case HostPairingController::STAGE_WAITING_FOR_CONTROLLER:
     case HostPairingController::STAGE_WAITING_FOR_CONTROLLER_AFTER_UPDATE: {
       desired_page = kPageWelcome;
@@ -79,12 +98,18 @@ void HostPairingScreen::PairingStageChanged(Stage new_stage) {
                          remora_controller_->GetConfirmationCode());
       break;
     }
+    case HostPairingController::STAGE_CONTROLLER_CONNECTION_ERROR: {
+      desired_page = kPageConnectionError;
+      ClearEnrollmentLocalState();
+      break;
+    }
     case HostPairingController::STAGE_SETUP_BASIC_CONFIGURATION: {
       desired_page = kPageSetupBasicConfiguration;
       break;
     }
     case HostPairingController::STAGE_SETUP_NETWORK_ERROR: {
       desired_page = kPageSetupNetworkError;
+      ClearEnrollmentLocalState();
       break;
     }
     case HostPairingController::STAGE_WAITING_FOR_CREDENTIALS: {
@@ -100,12 +125,14 @@ void HostPairingScreen::PairingStageChanged(Stage new_stage) {
     case HostPairingController::STAGE_ENROLLMENT_SUCCESS: {
       remora_controller_->RemoveObserver(this);
       Finish(WizardController::ENTERPRISE_ENROLLMENT_COMPLETED);
+      ClearEnrollmentLocalState();
       break;
     }
     case HostPairingController::STAGE_ENROLLMENT_ERROR: {
       // TODO(xdai): Maybe return to the Network Setup page?
       remora_controller_->RemoveObserver(this);
       desired_page = kPageEnrollmentError;
+      ClearEnrollmentLocalState();
       break;
     }
     default: