Add a method to read the Omaha experiment_labels value.

chrome/installer/util/google_update_settings_unittest.cc

 // 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.
 
 #include <windows.h>
 #include <shlwapi.h>  // For SHDeleteKey.
 
 #include "base/memory/scoped_ptr.h"
 #include "base/test/test_reg_util_win.h"
 #include "base/utf_string_conversions.h"
@@ skipping 108 matching lines @@
     BrowserDistribution* chrome =
         BrowserDistribution::GetSpecificDistribution(
             BrowserDistribution::CHROME_BROWSER);
 #if defined(GOOGLE_CHROME_BUILD)
     EXPECT_TRUE(chrome->ShouldSetExperimentLabels());
 
     EXPECT_TRUE(GoogleUpdateSettings::SetExperimentLabels(
         install == SYSTEM_INSTALL, kTestExperimentLabel));
 
     // Validate that something is written. Only worry about the label itself.
-    RegKey key;
     std::wstring value;
-    HKEY root = install == SYSTEM_INSTALL ?
-        HKEY_LOCAL_MACHINE : HKEY_CURRENT_USER;
-    string16 state_key = install == SYSTEM_INSTALL ?
-        chrome->GetStateMediumKey() : chrome->GetStateKey();
-
-    EXPECT_EQ(ERROR_SUCCESS,
-              key.Open(root, state_key.c_str(), KEY_QUERY_VALUE));
-    EXPECT_EQ(ERROR_SUCCESS,
-        key.ReadValue(google_update::kExperimentLabels, &value));
+    EXPECT_TRUE(GoogleUpdateSettings::ReadExperimentLabels(

[grt (UTC plus 2), 2013/01/09 18:49:51]

this tests that Set/Read round-trips properly, but no longer tests that they
write to the expected registry location.  how about leaving the previous
validation check in place?

[SteveT, 2013/01/09 19:36:10]

Makes sense, assuming we trust the validation code, which is sort of a repeat of
ReadExperimentsLabels, to some extent. :)

+        install == SYSTEM_INSTALL, &value));
     EXPECT_EQ(kTestExperimentLabel, value);
-    key.Close();
 
     // Now that the label is set, test the delete functionality. An empty label
     // should result in deleting the value.
     EXPECT_TRUE(GoogleUpdateSettings::SetExperimentLabels(
         install == SYSTEM_INSTALL, string16()));
-    EXPECT_EQ(ERROR_SUCCESS,
-              key.Open(root, state_key.c_str(), KEY_QUERY_VALUE));
-    EXPECT_EQ(ERROR_FILE_NOT_FOUND,
-        key.ReadValue(google_update::kExperimentLabels, &value));
-    key.Close();
+    EXPECT_FALSE(GoogleUpdateSettings::ReadExperimentLabels(
+        install == SYSTEM_INSTALL, &value));
 #else
     EXPECT_FALSE(chrome->ShouldSetExperimentLabels());

[grt (UTC plus 2), 2013/01/09 18:49:51]

add an expectation that ReadExperimentLables returns false here?

[SteveT, 2013/01/09 19:36:10]

Done.

 #endif  // GOOGLE_CHROME_BUILD
   }
 
   // Creates "ap" key with the value given as parameter. Also adds work
   // items to work_item_list given so that they can be rolled back later.
   bool CreateApKey(WorkItemList* work_item_list, const std::wstring& value) {
     HKEY reg_root = HKEY_CURRENT_USER;
     std::wstring reg_key = GetApKeyPath();
     work_item_list->AddCreateRegKeyWorkItem(reg_root, reg_key);
     work_item_list->AddSetRegValueWorkItem(reg_root, reg_key,
@@ skipping 817 matching lines @@
         StatsState(StatsState::kSystemLevel, StatsState::MULTI_INSTALL,
                    StatsState::FALSE_SETTING, StatsState::FALSE_SETTING),
         StatsState(StatsState::kSystemLevel, StatsState::MULTI_INSTALL,
                    StatsState::FALSE_SETTING, StatsState::TRUE_SETTING),
         StatsState(StatsState::kSystemLevel, StatsState::MULTI_INSTALL,
                    StatsState::TRUE_SETTING, StatsState::NO_SETTING),
         StatsState(StatsState::kSystemLevel, StatsState::MULTI_INSTALL,
                    StatsState::TRUE_SETTING, StatsState::FALSE_SETTING),
         StatsState(StatsState::kSystemLevel, StatsState::MULTI_INSTALL,
                    StatsState::TRUE_SETTING, StatsState::TRUE_SETTING)));