Chrome OS multi-profiles backend and UI.

chrome/browser/ui/webui/chromeos/login/signin_screen_handler.cc

 // Copyright (c) 2013 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.
 
 #include "chrome/browser/ui/webui/chromeos/login/signin_screen_handler.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/callback.h"
 #include "base/command_line.h"
@@ skipping 1355 matching lines @@
 void SigninScreenHandler::SendUserList(bool animated) {
   if (!delegate_)
     return;
 
   size_t max_non_owner_users = kMaxUsers - 1;
   size_t non_owner_count = 0;
 
   ListValue users_list;
   const UserList& users = delegate_->GetUsers();
 
+  // TODO(nkostylev): Move to a separate method in UserManager.
+  bool is_signin_to_add = BaseLoginDisplayHost::default_host() &&
+      UserManager::Get()->IsUserLoggedIn();
+
   bool single_user = users.size() == 1;
   for (UserList::const_iterator it = users.begin(); it != users.end(); ++it) {
     const std::string& email = (*it)->email();
+    if (is_signin_to_add && (*it)->is_logged_in()) {
+      // Skip all users that are already signed in.
+      continue;
+    }
+
     std::string owner;
     chromeos::CrosSettings::Get()->GetString(chromeos::kDeviceOwner, &owner);
     bool is_owner = (email == owner);
 
     if (non_owner_count < max_non_owner_users || is_owner) {
       DictionaryValue* user_dict = new DictionaryValue();
       FillUserDictionary(*it, is_owner, user_dict);
       bool is_public_account =
           ((*it)->GetType() == User::USER_TYPE_PUBLIC_ACCOUNT);
       bool signed_in = *it == UserManager::Get()->GetLoggedInUser();
       // Single user check here is necessary because owner info might not be
       // available when running into login screen on first boot.
       // See http://crosbug.com/12723
       user_dict->SetBoolean(kKeyCanRemove,
                             !single_user &&
                             !email.empty() &&
                             !is_owner &&
                             !is_public_account &&
-                            !signed_in);
+                            !signed_in &&
+                            !is_signin_to_add);
 
       users_list.Append(user_dict);
       if (!is_owner)
         ++non_owner_count;
     }
   }
 
   base::FundamentalValue animated_value(animated);
   base::FundamentalValue guest_value(delegate_->IsShowGuest());
   web_ui()->CallJavascriptFunction("login.AccountPickerScreen.loadUsers",
@@ skipping 340 matching lines @@
   if (!cros_settings)
     return false;
 
   // Offline login is allowed only when user pods are hidden.
   bool show_pods;
   cros_settings->GetBoolean(kAccountsPrefShowUserNamesOnSignIn, &show_pods);
   return !show_pods;
 }
 
 }  // namespace chromeos