Create a cros directory under client, and start moving things into it.

client/site_tests/login_CryptohomeIncognitoUnmounted/login_CryptohomeIncognitoUnmounted.py

 # Copyright (c) 2010 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.
 
-from autotest_lib.client.bin import chromeos_constants
 from autotest_lib.client.bin import site_cryptohome, site_ui_test
 from autotest_lib.client.common_lib import error, site_auth_server
+from autotest_lib.client.cros import constants as chromeos_constants
 
 class login_CryptohomeIncognitoUnmounted(site_ui_test.UITest):
     version = 1
 
 
     def __login_denier(self, handler, url_args):
         handler.send_response(403)
         handler.end_headers()
         handler.wfile.write('Error=BadAuthentication.')
 
 
     def start_authserver(self):
         self._authServer = site_auth_server.GoogleAuthServer(
             cl_responder=self.__login_denier)
         self._authServer.run()
 
         self.use_local_dns()
 
 
     def run_once(self):
         if (site_cryptohome.is_mounted(allow_fail=True) or
             not site_cryptohome.is_mounted_on_tmpfs(
                      device=chromeos_constants.CRYPTOHOME_INCOGNITO)):
             raise error.TestFail('CryptohomeIsMountedOnTmpfs should return '
                                  'True.')
         self.logout()
         # allow the command to fail, so we can handle the error here
         if site_cryptohome.is_mounted(allow_fail=True):
             raise error.TestFail('Expected cryptohome NOT to be mounted')