Detach the dependency from host_content_settings_map to extension.

chrome/browser/content_settings/content_settings_policy_provider.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/browser/content_settings/content_settings_policy_provider.h"
 
 #include <string>
 #include <vector>
 
 #include "base/json/json_reader.h"
@@ skipping 433 matching lines @@
 
 void PolicyProvider::ShutdownOnUIThread() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   RemoveAllObservers();
   if (!prefs_)
     return;
   pref_change_registrar_.RemoveAll();
   prefs_ = NULL;
 }
 
+std::string PolicyProvider::GetProviderName() const {
+  return "policy";
+}
+
+SettingSource PolicyProvider::GetSettingSource() const {
+  return SETTING_SOURCE_POLICY;
+}
+
 void PolicyProvider::OnPreferenceChanged(const std::string& name) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 
   if (name == prefs::kManagedDefaultCookiesSetting) {
     UpdateManagedDefaultSetting(CONTENT_SETTINGS_TYPE_COOKIES);
   } else if (name == prefs::kManagedDefaultImagesSetting) {
     UpdateManagedDefaultSetting(CONTENT_SETTINGS_TYPE_IMAGES);
   } else if (name == prefs::kManagedDefaultJavaScriptSetting) {
     UpdateManagedDefaultSetting(CONTENT_SETTINGS_TYPE_JAVASCRIPT);
   } else if (name == prefs::kManagedDefaultPluginsSetting) {
@@ skipping 24 matching lines @@
     ReadManagedDefaultSettings();
   }
 
   NotifyObservers(ContentSettingsPattern(),
                   ContentSettingsPattern(),
                   CONTENT_SETTINGS_TYPE_DEFAULT,
                   std::string());
 }
 
 }  // namespace content_settings