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

chrome/browser/ui/cocoa/profiles/profile_chooser_controller.mm

Index: chrome/browser/ui/cocoa/profiles/profile_chooser_controller.mm
diff --git a/chrome/browser/ui/cocoa/profiles/profile_chooser_controller.mm b/chrome/browser/ui/cocoa/profiles/profile_chooser_controller.mm
index b90c224829c609200234f69ba377c858882eb9f7..d829191697acc7ab292a9385f4e6ff0ab706bff5 100644
--- a/chrome/browser/ui/cocoa/profiles/profile_chooser_controller.mm
+++ b/chrome/browser/ui/cocoa/profiles/profile_chooser_controller.mm
@@ -30,10 +30,10 @@
 #include "chrome/browser/signin/signin_ui_util.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/browser_commands.h"
-#include "chrome/browser/ui/browser_dialogs.h"
 #include "chrome/browser/ui/browser_window.h"
 #include "chrome/browser/ui/chrome_pages.h"
 #include "chrome/browser/ui/chrome_style.h"
+#include "chrome/browser/ui/user_manager.h"
 #import "chrome/browser/ui/cocoa/hyperlink_text_view.h"
 #import "chrome/browser/ui/cocoa/info_bubble_view.h"
 #import "chrome/browser/ui/cocoa/info_bubble_window.h"
@@ -895,14 +895,18 @@ class ActiveProfileObserverBridge : public AvatarMenuObserver,
 }
 
 - (IBAction)showUserManager:(id)sender {
-  chrome::ShowUserManager(base::FilePath());
+  UserManager::Show(base::FilePath(),
+                    profiles::USER_MANAGER_NO_TUTORIAL,
+                    profiles::USER_MANAGER_SELECT_PROFILE_NO_ACTION);
   [self postActionPerformed:
       ProfileMetrics::PROFILE_DESKTOP_MENU_OPEN_USER_MANAGER];
 }
 
 - (IBAction)exitGuest:(id)sender {
   DCHECK(browser_->profile()->IsGuestSession());
-  chrome::ShowUserManager(base::FilePath());
+  UserManager::Show(base::FilePath(),
+                  profiles::USER_MANAGER_NO_TUTORIAL,

[Alexei Svitkine (slow), 2014/09/18 20:54:04]

Nit: Align.

[Mike Lerman, 2014/09/19 15:49:30]

Done.

+                  profiles::USER_MANAGER_SELECT_PROFILE_NO_ACTION);
   profiles::CloseGuestProfileWindows();
 }
 
@@ -976,8 +980,9 @@ class ActiveProfileObserverBridge : public AvatarMenuObserver,
 }
 
 - (IBAction)seeWhatsNew:(id)sender {
-  chrome::ShowUserManagerWithTutorial(
-      profiles::USER_MANAGER_TUTORIAL_OVERVIEW);
+  UserManager::Show(base::FilePath(),
+                    profiles::USER_MANAGER_TUTORIAL_OVERVIEW,
+                    profiles::USER_MANAGER_SELECT_PROFILE_NO_ACTION);
   ProfileMetrics::LogProfileNewAvatarMenuUpgrade(
       ProfileMetrics::PROFILE_AVATAR_MENU_UPGRADE_WHATS_NEW);
 }