Remove content::NotificationObserver dependency from most Prefs code.

chrome/browser/media_gallery/media_file_system_registry.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.
 
 // MediaFileSystemRegistry registers pictures directories and media devices as
 // File API filesystems and keeps track of the path to filesystem ID mappings.
 
 #ifndef CHROME_BROWSER_MEDIA_GALLERY_MEDIA_FILE_SYSTEM_REGISTRY_H_
 #define CHROME_BROWSER_MEDIA_GALLERY_MEDIA_FILE_SYSTEM_REGISTRY_H_
 
 #include <map>
 #include <string>
 #include <utility>
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/lazy_instance.h"
 #include "base/file_path.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
 #include "base/prefs/public/pref_change_registrar.h"
+#include "base/prefs/public/pref_observer.h"
 #include "base/system_monitor/system_monitor.h"
-#include "content/public/browser/notification_observer.h"
 #include "webkit/fileapi/media/mtp_device_file_system_config.h"
 
 class Profile;
 
 namespace content {
 class RenderViewHost;
 }
 
 namespace extensions {
 class Extension;
@@ skipping 40 matching lines @@
 
   // Revoke the passed |fsid|.
   virtual void RevokeFileSystem(const std::string& fsid) = 0;
 };
 
 typedef base::Callback<void(const std::vector<MediaFileSystemInfo>&)>
     MediaFileSystemsCallback;
 
 class MediaFileSystemRegistry
     : public base::SystemMonitor::DevicesChangedObserver,
-      public content::NotificationObserver {
+      public PrefObserver {
  public:
   // The instance is lazily created per browser process.
   static MediaFileSystemRegistry* GetInstance();
 
   // Passes to |callback| the list of media filesystem IDs and paths for a
   // given RVH. Called on the UI thread.
   void GetMediaFileSystemsForExtension(
       const content::RenderViewHost* rvh,
       const extensions::Extension* extension,
       const MediaFileSystemsCallback& callback);
@@ skipping 29 matching lines @@
   // ScopedMtpDeviceMapEntry.
   typedef std::map<const FilePath::StringType,
                    base::WeakPtr<ScopedMtpDeviceMapEntry> >
       MTPDeviceDelegateMap;
 #endif
 
   // Obtain an instance of this class via GetInstance().
   MediaFileSystemRegistry();
   virtual ~MediaFileSystemRegistry();
 
-  // NotificationObserver implementation.
-  virtual void Observe(int type,
-                       const content::NotificationSource& source,
-                       const content::NotificationDetails& details) OVERRIDE;
+  // PrefObserver implementation.
+  virtual void OnPreferenceChanged(PrefServiceBase* service,
+                                   const std::string& pref_name) OVERRIDE;
 
 #if defined(SUPPORT_MTP_DEVICE_FILESYSTEM)
   // Returns ScopedMtpDeviceMapEntry object for the given |device_location|.
   ScopedMtpDeviceMapEntry* GetOrCreateScopedMtpDeviceMapEntry(
       const FilePath::StringType& device_location);
 
   // Removes the ScopedMtpDeviceMapEntry associated with the given
   // |device_location|.
   void RemoveScopedMtpDeviceMapEntry(
       const FilePath::StringType& device_location);
@@ skipping 14 matching lines @@
 #endif
 
   scoped_ptr<MediaFileSystemContext> file_system_context_;
 
   DISALLOW_COPY_AND_ASSIGN(MediaFileSystemRegistry);
 };
 
 }  // namespace chrome
 
 #endif  // CHROME_BROWSER_MEDIA_GALLERY_MEDIA_FILE_SYSTEM_REGISTRY_H_