[MD settings] show icon when content settings are controlled by an extension

chrome/browser/ui/webui/policy_indicator_localized_strings_provider.cc

 // Copyright 2015 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/browser/ui/webui/policy_indicator_localized_strings_provider.h"
 
 #include "build/build_config.h"
 #include "chrome/grit/generated_resources.h"
 #include "content/public/browser/web_ui_data_source.h"
 
 namespace policy_indicator {
 
 void AddLocalizedStrings(content::WebUIDataSource* html_source) {
   html_source->AddLocalizedString("controlledSettingPolicy",
                                   IDS_OPTIONS_CONTROLLED_SETTING_POLICY);
   html_source->AddLocalizedString("controlledSettingRecommendedMatches",
                                   IDS_OPTIONS_CONTROLLED_SETTING_RECOMMENDED);
   html_source->AddLocalizedString(
       "controlledSettingRecommendedDiffers",
       IDS_OPTIONS_CONTROLLED_SETTING_HAS_RECOMMENDATION);
+  html_source->AddLocalizedString("controlledSettingExtension",
+                                  IDS_OPTIONS_CONTROLLED_SETTING_EXTENSION);
 #if defined(OS_CHROMEOS)
   html_source->AddLocalizedString("controlledSettingShared",
                                   IDS_OPTIONS_CONTROLLED_SETTING_SHARED);
   html_source->AddLocalizedString("controlledSettingOwner",
                                   IDS_OPTIONS_CONTROLLED_SETTING_OWNER);
 #endif
 }
 
 }  // namespace policy_indicator