[autotest] Ensure that ownership state is properly cleaned during test setup

client/cros/cros_ui_test.py

-# Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
+# 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.
 
 import dbus, logging, os, re, shutil, socket, sys
 import common
 import auth_server, constants, cryptohome, dns_server
 import cros_logging, cros_ui, login, ownership
 from autotest_lib.client.bin import test, utils
 from autotest_lib.client.common_lib import error
 from dbus.mainloop.glib import DBusGMainLoop
@@ skipping 149 matching lines @@
 
         # Mark /var/log/messages now; we'll run through all subsequent
         # log messages at the end of the test and log info about processes that
         # crashed.
         self._log_reader = cros_logging.LogReader()
         self._log_reader.set_start_by_current()
 
         if creds:
             self.start_authserver()
 
-        # Fake ownership unless the test is explicitly testing owner creation.
-        if not is_creating_owner and not os.access(
-            constants.OWNER_KEY_FILE, os.F_OK):
-            logging.info('Owner credentials not found. Faking ownership...')
-            self.__fake_ownership()
-            self.fake_owner = True
-
         if login.logged_in():
             login.attempt_logout()
 
+        # The UI must be taken down to ensure that no stale state persists.
+        cros_ui.stop()
         (self.username, self.password) = self.__resolve_creds(creds)
         # Ensure there's no stale cryptohome from previous tests.
         try:
             cryptohome.remove_vault(self.username)
         except cryptohome.ChromiumOSError as err:
             logging.error(err)
 
-        if is_creating_owner:
+        # Fake ownership unless the test is explicitly testing owner creation.
+        if not is_creating_owner:
+            logging.info('Faking ownership...')
+            self.__fake_ownership()
+            self.fake_owner = True
+        else:
             logging.info('Erasing stale owner state.')
             ownership.clear_ownership()
             self.fake_owner = False
+        cros_ui.start()
 
         login.refresh_login_screen()
         if self.auto_login:
             self.login(self.username, self.password)
             if is_creating_owner:
                 login.wait_for_ownership()
 
     def __fake_ownership(self):
         """Fake ownership by generating the necessary magic files."""
         # Determine the module directory.
@@ skipping 182 matching lines @@
 
         self.stop_authserver()
         self.__log_crashed_processes(self.crash_blacklist)
 
 
     def get_auth_endpoint_misses(self):
         if hasattr(self, '_authServer'):
             return self._authServer.get_endpoint_misses()
         else:
             return {}