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

chrome/browser/chromeos/login/webui_login_display.h

Index: chrome/browser/chromeos/login/webui_login_display.h
diff --git a/chrome/browser/chromeos/login/webui_login_display.h b/chrome/browser/chromeos/login/webui_login_display.h
index 699697235717bf34e70e5f9856969f9023f702a2..bc687261b2224edf3070e245242288faadec8513 100644
--- a/chrome/browser/chromeos/login/webui_login_display.h
+++ b/chrome/browser/chromeos/login/webui_login_display.h
@@ -10,7 +10,6 @@
 #include <vector>
 
 #include "base/memory/scoped_ptr.h"
-#include "base/memory/singleton.h"
 #include "chrome/browser/chromeos/login/login_display.h"
 #include "chrome/browser/chromeos/login/user_manager.h"
 #include "chrome/browser/ui/webui/chromeos/login/signin_screen_handler.h"
@@ -22,39 +21,13 @@ class Rect;
 
 namespace chromeos {
 // WebUI-based login UI implementation.
-// This class is a Singleton. It allows the LoginDisplayHost and LoginUIHandler
-// to access it without having to be coupled with each other. It is created with
-// NULL for the delegate and a 0-size rectangle for the background
-// bounds. Before use these values should be set to a sane value. When done with
-// the object, the ExistingUserController should call Destroy and not free the
-// pointer, where as accessing classes should do nothing with the pointer.
-//
-// Expected order of commands to setup for LoginDisplayHost:
-//   WebUILoginDisplay::GetInstance();
-//   set_delegate(delegate);
-//   set_background_bounds(background_bounds());
-//   Init();
-//
-// Expected order of commands to setup for LoginUIHandler:
-//   WebUILoginDisplay::GetInstance();
-//   set_login_handler(this);
-
 class WebUILoginDisplay : public LoginDisplay,
                           public SigninScreenHandlerDelegate {
  public:
+  explicit WebUILoginDisplay(LoginDisplay::Delegate* delegate);
   virtual ~WebUILoginDisplay();
 
-  // Singleton implementation:
-  static WebUILoginDisplay* GetInstance();
-
-  // Wrapper used to help in routing keyboard key presses into the login
-  // screen. This gets the Login Window widget from the Singleton, so that other
-  // classes don't need to know we are a Singleton
-  static views::Widget* GetLoginWindow();
-  views::Widget* LoginWindow();
-
   // LoginDisplay implementation:
-  virtual void Destroy() OVERRIDE;
   virtual void Init(const std::vector<UserManager::User>& users,
                     bool show_guest,
                     bool show_new_user) OVERRIDE;
@@ -83,28 +56,11 @@ class WebUILoginDisplay : public LoginDisplay,
       LoginDisplayWebUIHandler* webui_handler) OVERRIDE;
   virtual void ShowSigninScreenForCreds(const std::string& username,
                                         const std::string& password);
-
-  void set_login_window(views::Widget* login_window) {
-    login_window_ = login_window;
-  }
-
-  const std::vector<UserManager::User>& users() const {
-    return users_;
-  }
-
-  bool show_guest() const {
-    return show_guest_;
-  }
-
-  bool show_new_user() const {
-    return show_new_user_;
-  }
+  virtual const std::vector<UserManager::User>& GetUsers() const OVERRIDE;
+  virtual bool IsShowGuest() const OVERRIDE;
+  virtual bool IsShowNewUser() const OVERRIDE;
 
  private:
-  // Singleton implementation:
-  friend struct DefaultSingletonTraits<WebUILoginDisplay>;
-  WebUILoginDisplay();
-
   // Set of Users that are visible.
   std::vector<UserManager::User> users_;
 
@@ -114,9 +70,6 @@ class WebUILoginDisplay : public LoginDisplay,
   // Whether to show add new user.
   bool show_new_user_;
 
-  // Container of the screen we are displaying
-  views::Widget* login_window_;
-
   // Reference to the WebUI handling layer for the login screen
   LoginDisplayWebUIHandler* webui_handler_;