test: Clean up site_login.py a bit.

client/site_tests/login_LogoutProcessCleanup/login_LogoutProcessCleanup.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.
 
 import logging, os, time, utils
 from autotest_lib.client.bin import site_login, test
 from autotest_lib.client.common_lib import error
 
 class login_LogoutProcessCleanup(test.test):
     version = 1
@@ skipping 61 matching lines @@
     def setup(self):
         site_login.setup_autox(self)
 
 
     def run_once(self, script='autox_script.json', is_control=False,
             timeout=10):
         logged_in = site_login.logged_in()
 
         # Require that we start the test logged in
         if not logged_in:
-            if not site_login.attempt_login(self, script):
-                raise error.TestError('Could not login')
+            site_login.attempt_login(self, script)
 
         # Start a process as chronos.  This should get killed when logging out.
         bg_job = utils.BgJob('su chronos -c "sleep 3600"')
 
         session_manager = self.get_session_manager_pid()
         if session_manager == "":
             raise error.TestError('Could not find session manager pid')
 
         if not self.has_chronos_processes(session_manager):
             raise error.TestFail('Expected to find processes owned by chronos '
                 'that were not started by the session manager while logged in.')
 
-        if not site_login.attempt_logout():
-            raise error.TestError('Could not logout')
+        site_login.attempt_logout()
 
         logging.info('Logged out, searching for processes that should be dead')
 
         # Wait until we have a new session manager.  At that point, all
         # old processes should be dead.
         old_session_manager = session_manager
         while session_manager == "" or session_manager == old_session_manager:
             time.sleep(0.1)
             session_manager = self.get_session_manager_pid()
 
         if self.has_chronos_processes(session_manager):
             # Make sure the test job we started is dead.
             if bg_job.sp.returncode == None:
                 bg_job.sp.kill()
             raise error.TestFail('Expected NOT to find processes owned by '
                 'chronos that were not started by the session manager '
                 'while logged out.')
 
         # Reset the logged in state to how we started
         if logged_in:
-            if not site_login.attempt_login(self, script):
-                raise error.TestError('Could not login')
+            site_login.attempt_login(self, script)