Restart browser after Chromad enrollment

The current factoring of BrowserPolicyConnectorChromeOS only allows to
swap out the device policy provider at initialization time, not at run
time.  As a consequence, we end up with the wrong device policy provider
after Chromad enrollment.  A browser restart is the easiest way to fix
this.

BUG=681817

Review-Url: https://codereview.chromium.org/2842163002
Cr-Commit-Position: refs/heads/master@{#468592}

chrome/browser/chromeos/login/enrollment/enrollment_screen.cc

@@ -20,6 +20,7 @@
 #include "chrome/browser/chromeos/policy/browser_policy_connector_chromeos.h"
 #include "chrome/browser/chromeos/policy/enrollment_status_chromeos.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
+#include "chrome/browser/lifetime/application_lifetime.h"
 #include "chromeos/dbus/cryptohome_client.h"
 #include "chromeos/dbus/dbus_method_call_status.h"
 #include "chromeos/dbus/dbus_thread_manager.h"
@@ -248,6 +249,16 @@ void EnrollmentScreen::OnCancel() {
 void EnrollmentScreen::OnConfirmationClosed() {
   ClearAuth(base::Bind(&EnrollmentScreen::Finish, base::Unretained(this),
                        ScreenExitCode::ENTERPRISE_ENROLLMENT_COMPLETED));
+  // Restart browser to switch from DeviceCloudPolicyManagerChromeOS to
+  // DeviceActiveDirectoryPolicyManager.
+  if (g_browser_process->platform_part()
+          ->browser_policy_connector_chromeos()
+          ->IsActiveDirectoryManaged()) {
+    // TODO(tnagel): Refactor BrowserPolicyConnectorChromeOS so that device
+    // policy providers are only registered after enrollment has finished and
+    // thus the correct one can be picked without restarting the browser.
+    chrome::AttemptRestart();
+  }
 }
 
 void EnrollmentScreen::OnAdJoined(const std::string& realm) {