Move ownership of AppSorting from ExtensionPrefs to ExtensionSystem

extensions/shell/browser/shell_extensions_browser_client.cc

 // Copyright 2014 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 "extensions/shell/browser/shell_extensions_browser_client.h"
 
 #include "content/public/browser/browser_context.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/render_frame_host.h"
 #include "extensions/browser/api/extensions_api_client.h"
@@ skipping 138 matching lines @@
 }
 
 bool ShellExtensionsBrowserClient::DidVersionUpdate(BrowserContext* context) {
   // TODO(jamescook): We might want to tell extensions when app_shell updates.
   return false;
 }
 
 void ShellExtensionsBrowserClient::PermitExternalProtocolHandler() {
 }
 
-scoped_ptr<AppSorting> ShellExtensionsBrowserClient::CreateAppSorting(
-    content::BrowserContext* context) {
-  return scoped_ptr<AppSorting>(new NullAppSorting);
-}
-
 bool ShellExtensionsBrowserClient::IsRunningInForcedAppMode() {
   return false;
 }
 
 ApiActivityMonitor* ShellExtensionsBrowserClient::GetApiActivityMonitor(
     BrowserContext* context) {
   // app_shell doesn't monitor API function calls or events.
   return NULL;
 }
 
@@ skipping 67 matching lines @@
   api_client_.reset(api_client);
 }
 
 ExtensionWebContentsObserver*
 ShellExtensionsBrowserClient::GetExtensionWebContentsObserver(
     content::WebContents* web_contents) {
   return ShellExtensionWebContentsObserver::FromWebContents(web_contents);
 }
 
 }  // namespace extensions