Remove need to sign in to use the App Launcher.

ash/shell/app_list.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 <string>
 
 #include "ash/session/session_state_delegate.h"
 #include "ash/shell.h"
 #include "ash/shell/example_factory.h"
 #include "ash/shell/toplevel_window.h"
@@ skipping 236 matching lines @@
   virtual const Users& GetUsers() const OVERRIDE {
     return users_;
   }
 
   virtual bool ShouldCenterWindow() const OVERRIDE {
     return false;
   }
 
   virtual app_list::AppListModel* GetModel() OVERRIDE { return model_.get(); }
 
-  virtual app_list::SigninDelegate* GetSigninDelegate() OVERRIDE {
-    return NULL;
-  }
-
   virtual app_list::SpeechUIModel* GetSpeechUI() OVERRIDE {
     return &speech_ui_;
   }
 
   virtual void GetShortcutPathForApp(
       const std::string& app_id,
       const base::Callback<void(const base::FilePath&)>& callback) OVERRIDE {
     callback.Run(base::FilePath());
   }
 
@@ skipping 99 matching lines @@
 };
 
 }  // namespace
 
 app_list::AppListViewDelegate* CreateAppListViewDelegate() {
   return new ExampleAppListViewDelegate;
 }
 
 }  // namespace shell
 }  // namespace ash