[protector] Added UI for invalid Preferences backup case.

chrome/test/functional/protector.py

 #!/usr/bin/env python
 # Copyright (c) 2012 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.
 
 import pyauto_functional  # Must be imported first
 import pyauto
 import test_utils
 
 import json
@@ skipping 127 matching lines @@
 
   def _WritePreferences(self, prefs):
     """Writes new contents to the Preferences file.
 
     Args:
       prefs: dict() with new user preferences as returned by PrefsInfo.Prefs().
     """
     with open(os.path.join(self._profile_path, 'Preferences'), 'w') as f:
       json.dump(prefs, f)
 
+  def _InvalidatePreferencesBackup(self):
+    """Makes the Preferences backup invalid by clearing the signature."""
+    prefs = self._LoadPreferences()
+    prefs['backup']['_signature'] = 'INVALID'
+    self._WritePreferences(prefs)
+
   def _ChangeSessionStartupPrefs(self, startup_type, startup_urls=None,
                                  homepage=None):
     """Changes the session startup type and the list of URLs to load on startup.
 
     Args:
       startup_type: int with one of _SESSION_STARTUP_* values.
       startup_urls: list(str) with a list of URLs; if None, is left unchanged.
       homepage: unless None, the new value for homepage.
     """
     prefs = self._LoadPreferences()
@@ skipping 114 matching lines @@
     self.RestartBrowser(clear_profile=False)
     default_search = self._GetDefaultSearchEngine()
     self.assertEqual(old_default_search, default_search)
     # No longer showing the change.
     self.assertFalse(self.GetProtectorState()['showing_change'])
 
 # TODO(ivankr): more hijacking cases (remove the current default search engine,
 # add new search engines to the list, invalidate backup, etc).
 
 
+class ProtectorPreferencesTest(BaseProtectorTest):
+  """Generic test suite for Preferences protection."""
+
+  def testPreferencesBackupInvalid(self):
+    """Test for detecting invalid Preferences backup."""
+    self.RestartBrowser(
+        clear_profile=False,
+        pre_launch_hook=self._InvalidatePreferencesBackup)
+    # The change must be detected by Protector.
+    self.assertTrue(self.GetProtectorState()['showing_change'])
+    self.DiscardProtectorChange()
+    # Verify that a new tab with settings is opened.
+    info = self.GetBrowserInfo()
+    self.assertEqual(1, len(info['windows']))  # one window
+    self.assertEqual(2, len(info['windows'][0]['tabs']))  # 2 tabs
+    self.assertEqual('chrome://settings/', info['windows'][0]['tabs'][1]['url'])
+    # No longer showing the change.
+    self.assertFalse(self.GetProtectorState()['showing_change'])
+    self.RestartBrowser(clear_profile=False)
+    # Not showing the change after a restart
+    self.assertFalse(self.GetProtectorState()['showing_change'])
+
+
 class ProtectorSessionStartupTest(BaseProtectorTest):
   """Test suite for session startup changes detection with Protector enabled.
   """
   def testDetectSessionStartupChangeAndApply(self):
     """Test for detecting and applying a session startup pref change."""
     # Set startup prefs to restoring last open tabs.
     self.SetPrefs(pyauto.kRestoreOnStartup, self._SESSION_STARTUP_LAST)
     previous_url = 'chrome://version/'
     self.NavigateToURL(previous_url)
     # Restart browser with startup prefs set to open google.com.
@@ skipping 126 matching lines @@
                      self.GetPrefsInfo().Prefs(pyauto.kRestoreOnStartup))
     # Verify that open tabs are consistent with new prefs.
     info = self.GetBrowserInfo()
     self.assertEqual(1, len(info['windows']))  # one window
     self.assertEqual(1, len(info['windows'][0]['tabs']))  # one tab
     self.assertEqual(new_url, info['windows'][0]['tabs'][0]['url'])
 
 
 if __name__ == '__main__':
   pyauto_functional.Main()