Add a method to LoginUIService to open the sign in UI in a popup.

chrome/browser/ui/webui/signin/login_ui_service.h

 // 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.
 
 #ifndef CHROME_BROWSER_UI_WEBUI_SIGNIN_LOGIN_UI_SERVICE_H_
 #define CHROME_BROWSER_UI_WEBUI_SIGNIN_LOGIN_UI_SERVICE_H_
 #pragma once
 
 #include "base/basictypes.h"
 #include "chrome/browser/profiles/profile_keyed_service.h"
@@ skipping 21 matching lines @@
   LoginUIService();
   virtual ~LoginUIService();
 
   // Gets the currently active login UI, or null if no login UI is active.
   LoginUI* current_login_ui() const {
     return ui_;
   }
 
   // Sets the currently active login UI. It is illegal to call this if there is
   // already login UI visible.
+  // Fires chrome::NOTIFICATION_LOGIN_UI_CHANGED.
   void SetLoginUI(LoginUI* ui);
 
   // Called when login UI is closed. If the passed UI is the current login UI,
   // sets current_login_ui() to null.
+  // Fires chrome::NOTIFICATION_LOGIN_UI_CHANGED.
   void LoginUIClosed(LoginUI* ui);
 
   // Brings the login UI to the foreground, or if there is no login UI,
   // navigates to the login UI page in the given browser.
   // Virtual for mocking purposes.
   virtual void ShowLoginUI(Browser* browser);
 
+  // Same as ShowLoginUI but opens a popup with the login UI instead of a
+  // new tab.
+  // Note that if an existing login UI is already open, this method will focus
+  // that UI even though it is not a popup.
+  virtual void ShowLoginDialogUI(Browser* browser);
+
  private:
+  void FireLoginUIChanged() const;
+
   // Weak pointer to the currently active login UI, or null if none.
   LoginUI* ui_;
 
   DISALLOW_COPY_AND_ASSIGN(LoginUIService);
 };
 
 #endif  // CHROME_BROWSER_UI_WEBUI_SIGNIN_LOGIN_UI_SERVICE_H_