Force migrate all clients from multi-install back to single-install.

chrome/installer/util/master_preferences_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.
 //
 // Unit tests for master preferences related methods.
 
 #include "chrome/installer/util/master_preferences.h"
 
 #include <stddef.h>
 
@@ skipping 308 matching lines @@
 
   base::CommandLine chrome_install(
       base::CommandLine::FromString(chrome_cmd.str()));
 
   installer::MasterPreferences pref_chrome(chrome_install);
 
   EXPECT_FALSE(pref_chrome.is_multi_install());
   EXPECT_TRUE(pref_chrome.install_chrome());
 }
 
-TEST_F(MasterPreferencesTest, TestMultiInstallConfig) {
+TEST_F(MasterPreferencesTest, TestMultiInstallIgnoredConfig) {
   using installer::switches::kMultiInstall;
   using installer::switches::kChrome;
 
   std::wstringstream chrome_cmd, cf_cmd, chrome_cf_cmd;
   chrome_cmd << "setup.exe --" << kMultiInstall << " --" << kChrome;
 
   base::CommandLine chrome_install(
       base::CommandLine::FromString(chrome_cmd.str()));
 
   installer::MasterPreferences pref_chrome(chrome_install);
 
-  EXPECT_TRUE(pref_chrome.is_multi_install());
+  EXPECT_FALSE(pref_chrome.is_multi_install());
   EXPECT_TRUE(pref_chrome.install_chrome());
 }
 
 TEST_F(MasterPreferencesTest, EnforceLegacyCreateAllShortcutsFalse) {
   static const char kCreateAllShortcutsFalsePrefs[] =
       "{"
       "  \"distribution\": {"
       "     \"create_all_shortcuts\": false"
       "  }"
       "}";
@@ skipping 101 matching lines @@
   }
   {
     ScopedGoogleUpdateIsMachine env_setter("2");
     installer::MasterPreferences prefs(
         base::CommandLine(base::FilePath(FILE_PATH_LITERAL("setup.exe"))));
     bool value = false;
     prefs.GetBool(installer::master_preferences::kSystemLevel, &value);
     EXPECT_FALSE(value);
   }
 }