Revert of Remove deprecated extension notification from content_settings

chrome/browser/content_settings/content_settings_internal_extension_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_INTERNAL_EXTENSION_PROVIDER_H_
 #define CHROME_BROWSER_CONTENT_SETTINGS_CONTENT_SETTINGS_INTERNAL_EXTENSION_PROVIDER_H_
 
 #include "base/memory/scoped_ptr.h"
 #include "base/synchronization/lock.h"
 #include "chrome/browser/content_settings/content_settings_observable_provider.h"
 #include "chrome/browser/content_settings/content_settings_origin_identifier_value_map.h"
 #include "components/content_settings/core/common/content_settings.h"
 #include "content/public/browser/notification_observer.h"
 #include "content/public/browser/notification_registrar.h"
-#include "extensions/browser/extension_registry_observer.h"
 
 class ExtensionService;
 
 namespace extensions {
 class Extension;
-class ExtensionRegistry;
 }
 
 namespace content_settings {
 
 // A content settings provider which disables certain plugins for platform apps.
 class InternalExtensionProvider : public ObservableProvider,
-                                  public content::NotificationObserver,
-                                  public extensions::ExtensionRegistryObserver {
+                            public content::NotificationObserver {
  public:
   explicit InternalExtensionProvider(ExtensionService* extension_service);
 
   virtual ~InternalExtensionProvider();
 
   // ProviderInterface methods:
   virtual RuleIterator* GetRuleIterator(
       ContentSettingsType content_type,
       const ResourceIdentifier& resource_identifier,
       bool incognito) const OVERRIDE;
 
   virtual bool SetWebsiteSetting(
       const ContentSettingsPattern& primary_pattern,
       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;
 
   // content::NotificationObserver implementation.
   virtual void Observe(int type,
                        const content::NotificationSource& source,
                        const content::NotificationDetails& details) OVERRIDE;
-
-  // extensions::ExtensionRegistryObserver implementation.
-  virtual void OnExtensionLoaded(
-      content::BrowserContext* browser_context,
-      const extensions::Extension* extension) OVERRIDE;
-  virtual void OnExtensionUnloaded(
-      content::BrowserContext* browser_context,
-      const extensions::Extension* extension,
-      extensions::UnloadedExtensionInfo::Reason reason) OVERRIDE;
-
  private:
   void SetContentSettingForExtension(const extensions::Extension* extension,
                                      ContentSetting setting);
   void SetContentSettingForExtensionAndResource(
       const extensions::Extension* extension,
       const ResourceIdentifier& resource,
       ContentSetting setting);
 
   OriginIdentifierValueMap value_map_;
 
   // Used around accesses to the |value_map_| list to guarantee thread safety.
   mutable base::Lock lock_;
   scoped_ptr<content::NotificationRegistrar> registrar_;
 
-  extensions::ExtensionRegistry* extension_registry_;  // Not owned.
-
   DISALLOW_COPY_AND_ASSIGN(InternalExtensionProvider);
 };
 
 }  // namespace content_settings
 
 #endif  // CHROME_BROWSER_CONTENT_SETTINGS_CONTENT_SETTINGS_INTERNAL_EXTENSION_PROVIDER_H_