[login_manager] Fix race condition that caused ownership to never work

session_manager_service.cc

 // Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "login_manager/session_manager_service.h"
 
 #include <dbus/dbus-glib-lowlevel.h>
 #include <errno.h>
 #include <glib.h>
 #include <grp.h>
@@ skipping 1121 matching lines @@
   if (VerifyHelper(was_signed, decoded.c_str(), decoded.length()) != SUCCESS) {
     LOG(ERROR) << "Owner pref signature could not be verified.";
     return FALSE;
   }
   return value == current_user_;
 }
 
 gboolean SessionManagerService::CurrentUserHasOwnerKey(
     const std::vector<uint8>& pub_key,
     GError** error) {
+  if (!nss_->MightHaveKeys())
+    return FALSE;
   if (!nss_->OpenUserDB()) {
     const char msg[] = "Could not open the current user's NSS database.";
     LOG(ERROR) << msg;
     system_->SetGError(error, CHROMEOS_LOGIN_ERROR_NO_USER_NSSDB, msg);
     return FALSE;
   }
   if (!nss_->GetPrivateKey(pub_key)) {
     const char msg[] = "Could not verify that public key belongs to the owner.";
     LOG(WARNING) << msg;
     system_->SetGError(error, CHROMEOS_LOGIN_ERROR_ILLEGAL_PUBKEY, msg);
@@ skipping 200 matching lines @@
       arg_list.push_back(args[i_arg]);
     }
   }
   if (arg_list.size()) {
     arg_lists.push_back(arg_list);
   }
   return arg_lists;
 }
 
 }  // namespace login_manager