[cros,de-hack] Get rid of singleton for the WebUILoginScreen.

chrome/browser/chromeos/login/existing_user_controller.cc

 // Copyright (c) 2011 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/chromeos/login/existing_user_controller.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/command_line.h"
 #include "base/logging.h"
@@ skipping 62 matching lines @@
 
 // static
 ExistingUserController* ExistingUserController::current_controller_ = NULL;
 
 ////////////////////////////////////////////////////////////////////////////////
 // ExistingUserController, public:
 
 ExistingUserController::ExistingUserController(LoginDisplayHost* host)
     : login_status_consumer_(NULL),
       host_(host),
+      login_display_(host_->CreateLoginDisplay(this)),
       num_login_attempts_(0),
       user_settings_(new UserCrosSettingsProvider),
       weak_factory_(this),
       is_owner_login_(false) {
   DCHECK(current_controller_ == NULL);
   current_controller_ = this;
 
-  login_display_ = host_->CreateLoginDisplay(this);
-
   registrar_.Add(this,
                  chrome::NOTIFICATION_LOGIN_USER_IMAGE_CHANGED,
                  content::NotificationService::AllSources());
 }
 
 void ExistingUserController::Init(const UserVector& users) {
   UserVector filtered_users;
   if (UserCrosSettingsProvider::cached_show_users_on_signin()) {
     for (size_t i = 0; i < users.size(); ++i)
       // TODO(xiyuan): Clean user profile whose email is not in whitelist.
@@ skipping 35 matching lines @@
 // ExistingUserController, private:
 
 ExistingUserController::~ExistingUserController() {
   LoginUtils::Get()->DelegateDeleted(this);
 
   if (current_controller_ == this) {
     current_controller_ = NULL;
   } else {
     NOTREACHED() << "More than one controller are alive.";
   }
-  DCHECK(login_display_ != NULL);
-  login_display_->Destroy();
-  login_display_ = NULL;
+  DCHECK(login_display_.get());
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // ExistingUserController, LoginDisplay::Delegate implementation:
 //
 
 void ExistingUserController::CreateAccount() {
   guest_mode_url_ =
       google_util::AppendGoogleLocaleParam(GURL(kCreateAccountURL));
   LoginAsGuest();
@@ skipping 433 matching lines @@
     cryptohomed->AsyncSetOwnerUser(
         UserCrosSettingsProvider::cached_owner(), NULL);
 
     // Do not invoke AsyncDoAutomaticFreeDiskSpaceControl(NULL) here
     // so it does not delay the following mount. Cleanup will be
     // started in Cryptohomed by timer.
   }
 }
 
 }  // namespace chromeos