Reduce flakes in the mini_installer test.

chrome/test/mini_installer/test_installer.py

 # Copyright 2013 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """This script tests the installer with test cases specified in the config file.
 
 For each test case, it checks that the machine states after the execution of
 each command match the expected machine states. For more details, take a look at
 the design documentation at http://goo.gl/Q0rGM6
 """
 
 import argparse
 import json
 import os
 import subprocess
 import sys
 import time
 import unittest
+import _winreg
 
 from variable_expander import VariableExpander
 import verifier_runner
 
 
 class Config:
   """Describes the machine states, actions, and test cases.
 
   Attributes:
     states: A dictionary where each key is a state name and the associated value
@@ skipping 108 matching lines @@
     variable_expander: A VariableExpander object.
   """
   expanded_command = variable_expander.Expand(command)
   script_dir = os.path.dirname(os.path.abspath(__file__))
   exit_status = subprocess.call(expanded_command, shell=True, cwd=script_dir)
   if exit_status != 0:
     raise Exception('Command %s returned non-zero exit status %s' % (
         expanded_command, exit_status))
 
 
+def DeleteGoogleUpdateRegistration(system_level, variable_expander):
+  """Deletes Chrome's registration with Google Update.
+
+  Args:
+    system_level: True if system-level Chrome is to be deleted.
+    variable_expander: A VariableExpander object.
+  """
+  root = (_winreg.HKEY_LOCAL_MACHINE if system_level
+          else _winreg.HKEY_CURRENT_USER)
+  key_name = variable_expander.Expand('$CHROME_UPDATE_REGISTRY_SUBKEY')
+  try:
+    key_handle = _winreg.OpenKey(root, key_name, 0,
+                                 _winreg.KEY_SET_VALUE |
+                                 _winreg.KEY_WOW64_32KEY)
+    _winreg.DeleteValue(key_handle, 'pv')
+  except WindowsError:
+    # The key isn't present, so there is no value to delete.
+    pass
+
+
 def RunCleanCommand(force_clean, variable_expander):
   """Puts the machine in the clean state (i.e. Chrome not installed).
 
   Args:
     force_clean: A boolean indicating whether to force cleaning existing
         installations.
     variable_expander: A VariableExpander object.
   """
-  # TODO(sukolsak): Read the clean state from the config file and clean
-  # the machine according to it.
   # TODO(sukolsak): Handle Chrome SxS installs.
-  commands = []
   interactive_option = '--interactive' if not force_clean else ''
-  for level_option in ('', '--system-level'):
-    commands.append('python uninstall_chrome.py '
-                    '--chrome-long-name="$CHROME_LONG_NAME" '
-                    '--no-error-if-absent %s %s' %
-                    (level_option, interactive_option))
-  RunCommand(' && '.join(commands), variable_expander)
+  for system_level in (False, True):
+    level_option = '--system-level' if system_level else ''
+    command = ('python uninstall_chrome.py '
+               '--chrome-long-name="$CHROME_LONG_NAME" '
+               '--no-error-if-absent %s %s' %
+               (level_option, interactive_option))
+    RunCommand(command, variable_expander)
+    if force_clean:
+      DeleteGoogleUpdateRegistration(system_level, variable_expander)
 
 
 def MergePropertyDictionaries(current_property, new_property):
   """Merges the new property dictionary into the current property dictionary.
 
   This is different from general dictionary merging in that, in case there are
   keys with the same name, we merge values together in the first level, and we
   override earlier values in the second level. For more details, take a look at
   http://goo.gl/uE0RoR
 
@@ skipping 188 matching lines @@
     trie[path] = value
     return
   directory, rest = path.split(TEST_SEPARATOR, 1)
   if directory not in trie:
     trie[directory] = {}
   _AddPathToTrie(trie[directory], rest, value)
 
 
 if __name__ == '__main__':
   sys.exit(main())