Detach the dependency from host_content_settings_map to extension.

chrome/browser/content_settings/content_settings_pref_provider.h

 // 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.
 
 #ifndef CHROME_BROWSER_CONTENT_SETTINGS_CONTENT_SETTINGS_PREF_PROVIDER_H_
 #define CHROME_BROWSER_CONTENT_SETTINGS_CONTENT_SETTINGS_PREF_PROVIDER_H_
 
 // A content settings provider that takes its settings out of the pref service.
 
 #include <vector>
@@ skipping 38 matching lines @@
       const ContentSettingsPattern& secondary_pattern,
       ContentSettingsType content_type,
       const ResourceIdentifier& resource_identifier,
       base::Value* value) OVERRIDE;
 
   virtual void ClearAllContentSettingsRules(
       ContentSettingsType content_type) OVERRIDE;
 
   virtual void ShutdownOnUIThread() OVERRIDE;
 
+  virtual std::string GetProviderName() const OVERRIDE;
+
+  virtual SettingSource GetSettingSource() const OVERRIDE;
+
   // Records the last time the given pattern has used a certain content setting.
   void UpdateLastUsage(const ContentSettingsPattern& primary_pattern,
                        const ContentSettingsPattern& secondary_pattern,
                        ContentSettingsType content_type);
 
   base::Time GetLastUsage(const ContentSettingsPattern& primary_pattern,
                           const ContentSettingsPattern& secondary_pattern,
                           ContentSettingsType content_type);
 
   // Gains ownership of |clock|.
@@ skipping 51 matching lines @@
 
   // Used around accesses to the value map objects to guarantee thread safety.
   mutable base::Lock lock_;
 
   DISALLOW_COPY_AND_ASSIGN(PrefProvider);
 };
 
 }  // namespace content_settings
 
 #endif  // CHROME_BROWSER_CONTENT_SETTINGS_CONTENT_SETTINGS_PREF_PROVIDER_H_