Update AutoImport to import nothing by default (in absence of policy and master_prefs).

chrome/installer/util/master_preferences.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 "chrome/installer/util/master_preferences.h"
 
 #include <stddef.h>
 
 #include "base/environment.h"
 #include "base/files/file_util.h"
@@ skipping 208 matching lines @@
   // do_not_create_(desktop|quick_launch)_shortcut to true.
   bool create_all_shortcuts = true;
   GetBool(kCreateAllShortcuts, &create_all_shortcuts);
   if (!create_all_shortcuts) {
     distribution_->SetBoolean(
         installer::master_preferences::kDoNotCreateDesktopShortcut, true);
     distribution_->SetBoolean(
         installer::master_preferences::kDoNotCreateQuickLaunchShortcut, true);
   }
 
+  // Deprecated boolean import master preferences now mapped to their duplicates
+  // in prefs::.
+  static constexpr char kDistroImportHistoryPref[] = "import_history";
+  static constexpr char kDistroImportHomePagePref[] = "import_home_page";
+  static constexpr char kDistroImportSearchPref[] = "import_search_engine";
+  static constexpr char kDistroImportBookmarksPref[] = "import_bookmarks";
+
+  static constexpr struct {
+    const char* old_distro_pref_path;
+    const char* modern_pref_path;
+  } kLegacyDistroImportPrefMappings[] = {
+      {kDistroImportBookmarksPref, prefs::kImportBookmarks},
+      {kDistroImportHistoryPref, prefs::kImportHistory},
+      {kDistroImportHomePagePref, prefs::kImportHomepage},
+      {kDistroImportSearchPref, prefs::kImportSearchEngine},
+  };
+
+  for (const auto& mapping : kLegacyDistroImportPrefMappings) {
+    bool value = false;
+    if (GetBool(mapping.old_distro_pref_path, &value))
+      master_dictionary_->SetBoolean(mapping.modern_pref_path, value);
+  }
+
 #if BUILDFLAG(ENABLE_RLZ)
   // Map the RLZ ping delay shipped in the distribution dictionary into real
   // prefs.
   static constexpr char kDistroPingDelay[] = "ping_delay";
   int rlz_ping_delay = 0;
   if (GetInt(kDistroPingDelay, &rlz_ping_delay))
     master_dictionary_->SetInteger(prefs::kRlzPingDelaySeconds, rlz_ping_delay);
 #endif  // BUILDFLAG(ENABLE_RLZ)
 }
 
@@ skipping 51 matching lines @@
   }
   return result;
 }
 
 // static
 const MasterPreferences& MasterPreferences::ForCurrentProcess() {
   return g_master_preferences.Get();
 }
 
 }  // namespace installer