Split ExtensionSystem interface from ExtensionSystemImpl implementation, part 1.

chrome/browser/media_galleries/media_file_system_registry.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/media_galleries/media_file_system_registry.h"
 
 #include <set>
 #include <vector>
 
 #include "base/bind.h"
 #include "base/callback.h"
 #include "base/files/file_path.h"
 #include "base/prefs/pref_service.h"
 #include "base/stl_util.h"
 #include "chrome/browser/extensions/extension_service.h"
-#include "chrome/browser/extensions/extension_system.h"
 #include "chrome/browser/media_galleries/fileapi/mtp_device_map_service.h"
 #include "chrome/browser/media_galleries/imported_media_gallery_registry.h"
 #include "chrome/browser/media_galleries/media_file_system_context.h"
 #include "chrome/browser/media_galleries/media_galleries_dialog_controller.h"
 #include "chrome/browser/media_galleries/media_galleries_histograms.h"
 #include "chrome/browser/media_galleries/media_galleries_preferences_factory.h"
 #include "chrome/browser/media_galleries/media_scan_manager.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/storage_monitor/media_storage_util.h"
 #include "chrome/browser/storage_monitor/storage_monitor.h"
 #include "chrome/common/chrome_paths.h"
 #include "chrome/common/extensions/extension_constants.h"
 #include "chrome/common/pref_names.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/navigation_details.h"
 #include "content/public/browser/render_process_host.h"
 #include "content/public/browser/render_process_host_observer.h"
 #include "content/public/browser/render_view_host.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/browser/web_contents_observer.h"
+#include "extensions/browser/extension_system.h"
 #include "extensions/common/extension.h"
 #include "extensions/common/extension_set.h"
 #include "webkit/browser/fileapi/isolated_context.h"
 #include "webkit/common/fileapi/file_system_types.h"
 
 using content::BrowserThread;
 using content::NavigationController;
 using content::RenderProcessHost;
 using content::WebContents;
 using fileapi::IsolatedContext;
@@ skipping 683 matching lines @@
   DCHECK_EQ(1U, erase_count);
   if (extension_hosts->second.empty()) {
     // When a profile has no ExtensionGalleriesHosts left, remove the
     // matching gallery-change-watcher since it is no longer needed. Leave the
     // |extension_hosts| entry alone, since it indicates the profile has been
     // previously used.
     MediaGalleriesPreferences* preferences = GetPreferences(profile);
     preferences->RemoveGalleryChangeObserver(this);
   }
 }