Creating supervised users restricted for regular users if they are supervised.

chrome/browser/chromeos/login/users/chrome_user_manager.h

Index: chrome/browser/chromeos/login/users/chrome_user_manager.h
diff --git a/chrome/browser/chromeos/login/users/chrome_user_manager.h b/chrome/browser/chromeos/login/users/chrome_user_manager.h
index c6a74eb9868e5cef59e605a4d56825d51ea621e7..66a0bda5ee24b6f0c95cb4cf1971d6de785afcc7 100644
--- a/chrome/browser/chromeos/login/users/chrome_user_manager.h
+++ b/chrome/browser/chromeos/login/users/chrome_user_manager.h
@@ -6,6 +6,7 @@
 #define CHROME_BROWSER_CHROMEOS_LOGIN_USERS_CHROME_USER_MANAGER_H_
 
 #include "base/basictypes.h"
+#include "components/user_manager/user.h"
 #include "components/user_manager/user_manager_base.h"
 
 namespace base {
@@ -30,6 +31,11 @@ class ChromeUserManager : public user_manager::UserManagerBase {
   // yet initialized.
   static ChromeUserManager* Get();
 
+  // Helper method for sorting out of user list only users that can create
+  // supervised users.
+  static user_manager::UserList GetUsersAllowedAsSupervisedUserManagers(
+      const user_manager::UserList& user_list);
+
   virtual MultiProfileUserController* GetMultiProfileUserController() = 0;
   virtual UserImageManager* GetUserImageManager(const std::string& user_id) = 0;
   virtual SupervisedUserManager* GetSupervisedUserManager() = 0;