app_sorting() calls should go via ExtensionSystem intsead of prefs.

chrome/browser/ui/app_list/extension_app_item.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/ui/app_list/extension_app_item.h"
 
 #include "base/prefs/pref_service.h"
 #include "chrome/browser/extensions/extension_util.h"
 #include "chrome/browser/extensions/launch_util.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/ui/app_list/app_context_menu.h"
 #include "chrome/browser/ui/app_list/app_list_controller_delegate.h"
 #include "chrome/browser/ui/app_list/app_list_service.h"
 #include "chrome/browser/ui/extensions/extension_enable_flow.h"
 #include "chrome/browser/ui/host_desktop.h"
 #include "chrome/common/extensions/extension_constants.h"
 #include "chrome/common/extensions/extension_metrics.h"
 #include "content/public/browser/user_metrics.h"
 #include "extensions/browser/app_sorting.h"
 #include "extensions/browser/extension_prefs.h"
 #include "extensions/browser/extension_registry.h"
+#include "extensions/browser/extension_system.h"
 #include "extensions/common/extension.h"
 #include "extensions/common/extension_icon_set.h"
 #include "extensions/common/manifest_handlers/icons_handler.h"
 #include "extensions/common/manifest_url_handlers.h"
 #include "grit/theme_resources.h"
 #include "sync/api/string_ordinal.h"
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/gfx/canvas.h"
 #include "ui/gfx/color_utils.h"
 #include "ui/gfx/geometry/rect.h"
@@ skipping 62 matching lines @@
     canvas->DrawImageInt(
         gfx::ImageSkia(masking_canvas->ExtractImageRep()), 0, 0, masking_paint);
   }
 
   gfx::ImageSkia icon_;
 
   DISALLOW_COPY_AND_ASSIGN(RoundedCornersImageSource);
 };
 
 extensions::AppSorting* GetAppSorting(Profile* profile) {
-  return extensions::ExtensionPrefs::Get(profile)->app_sorting();
+  return extensions::ExtensionSystem::Get(profile)->app_sorting();
 }
 
 gfx::ImageSkia CreateDisabledIcon(const gfx::ImageSkia& icon) {
   const color_utils::HSL shift = {-1, 0, 0.6};
   return gfx::ImageSkiaOperations::CreateHSLShiftedImage(icon, shift);
 }
 
 }  // namespace
 
 ExtensionAppItem::ExtensionAppItem(
@@ skipping 239 matching lines @@
   const syncer::StringOrdinal& launch =
      GetAppSorting(profile_)->GetAppLaunchOrdinal(extension_id_);
   set_position(syncer::StringOrdinal(
       page.ToInternalValue() + launch.ToInternalValue()));
 }
 
 AppListControllerDelegate* ExtensionAppItem::GetController() {
   return AppListService::Get(chrome::GetActiveDesktop())->
       GetControllerDelegate();
 }