Rollback option put behind the flag.

BUG=368860

Review URL: https://codereview.chromium.org/267393011

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@269753 0039d316-1c4b-4281-b951-d872f2087c98
 void ResetScreenHandler::UpdateStatusChanged(
     const UpdateEngineClient::Status& status) {
  VLOG(1) << "Update status change to " << status.status;
   if (status.status == UpdateEngineClient::UPDATE_STATUS_ERROR) {
     base::DictionaryValue params;
    params.SetInteger("uiState", kErrorUIStateRollback);
    ShowScreen(OobeUI::kScreenErrorMessage, &params);
  } else if (status.status ==
      UpdateEngineClient::UPDATE_STATUS_UPDATED_NEED_REBOOT) {
    DBusThreadManager::Get()->GetPowerManagerClient()->RequestRestart();
  }
}

 void ResetScreenHandler::UpdateStatusChanged(
     const UpdateEngineClient::Status& status) {
   if (status.status == UpdateEngineClient::UPDATE_STATUS_ERROR) {
     base::DictionaryValue params;
    params.SetInteger("uiState", kErrorUIStateRollback);
    ShowScreen(OobeUI::kScreenErrorMessage, &params);
  } else if (status.status ==
      UpdateEngineClient::UPDATE_STATUS_UPDATED_NEED_REBOOT) {
    DBusThreadManager::Get()->GetPowerManagerClient()->RequestRestart();
  }
}
