Access to Chrome via the System Tray should go through the User Manager.

chrome/browser/ui/browser_dialogs.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_BROWSER_DIALOGS_H_
 #define CHROME_BROWSER_UI_BROWSER_DIALOGS_H_
 
 #include "base/callback.h"
 #include "chrome/browser/profiles/profile_window.h"
 #include "content/public/common/signed_certificate_timestamp_id_and_status.h"
@@ skipping 80 matching lines @@
 content::ColorChooser* ShowColorChooser(content::WebContents* web_contents,
                                         SkColor initial_color);
 
 void ShowProfileSigninConfirmationDialog(
     Browser* browser,
     content::WebContents* web_contents,
     Profile* profile,
     const std::string& username,
     ui::ProfileSigninConfirmationDelegate* delegate);
 
-
-// Shows the Desktop User Manager with the |profile_path_to_focus| user focused.
-void ShowUserManager(const base::FilePath& profile_path_to_focus);
-
-// Shows the Desktop User Manager with a specific |tutorial|.
-void ShowUserManagerWithTutorial(profiles::UserManagerTutorialMode tutorial);
-
-// Hides the User Manager.
-void HideUserManager();
-
 // Shows the Signed Certificate Timestamps viewer, to view the signed
 // certificate timestamps in |sct_ids_list|
 void ShowSignedCertificateTimestampsViewer(
     content::WebContents* web_contents,
     const content::SignedCertificateTimestampIDStatusList& sct_ids_list);
 
 // Shows the ManagePasswords bubble for a particular |web_contents|.
 void ShowManagePasswordsBubble(content::WebContents* web_contents);
 
 // Closes the bubble if it's shown for |web_contents|.
 void CloseManagePasswordsBubble(content::WebContents* web_contents);
 
 }  // namespace chrome
 
 #endif  // CHROME_BROWSER_UI_BROWSER_DIALOGS_H_