Add a SigninAllowed policy.

chrome/browser/ui/sync/one_click_signin_helper.cc

 // 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.
 
 #include "chrome/browser/ui/sync/one_click_signin_helper.h"
 
 #include <algorithm>
 #include <functional>
 #include <utility>
 #include <vector>
@@ skipping 372 matching lines @@
     *error_message_id = 0;
 
   if (!web_contents)
     return false;
 
   if (web_contents->GetBrowserContext()->IsOffTheRecord())
     return false;
 
   Profile* profile =
       Profile::FromBrowserContext(web_contents->GetBrowserContext());
-  if (!profile)
+  if (!profile || !profile->IsSigninAllowed())
     return false;
 
   if (can_offer_for == CAN_OFFER_FOR_INTERSTITAL_ONLY &&
       !profile->GetPrefs()->GetBoolean(prefs::kReverseAutologinEnabled))
     return false;
 
   if (!SigninManager::AreSigninCookiesAllowed(profile))
     return false;
 
   if (!email.empty()) {
@@ skipping 88 matching lines @@
     return DONT_OFFER;
 
   if (!SyncPromoUI::UseWebBasedSigninFlow())
     return DONT_OFFER;
 
   // Check for incognito before other parts of the io_data, since those
   // members may not be initalized.
   if (io_data->is_incognito())
     return DONT_OFFER;
 
+  if (!SigninManager::IsSigninAllowedOnIOThread(io_data))
+    return DONT_OFFER;
+
   if (!io_data->reverse_autologin_enabled()->GetValue())
     return DONT_OFFER;
 
   if (!io_data->google_services_username()->GetValue().empty())
     return DONT_OFFER;
 
   if (!SigninManager::AreSigninCookiesAllowed(io_data->GetCookieSettings()))
     return DONT_OFFER;
 
   // The checks below depend on chrome already knowing what account the user
@@ skipping 433 matching lines @@
         break;
     }
   }
 
   RedirectToNTP();
 }
 
 void OneClickSigninHelper::SigninSuccess() {
   RedirectToNTP();
 }