Add policy provider that would filter extensions/apps allowed on the

chrome/browser/extensions/extension_system_impl.cc

 // Copyright 2014 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/extensions/extension_system_impl.h"
 
 #include <algorithm>
 
 #include "base/base_switches.h"
 #include "base/bind.h"
@@ skipping 48 matching lines @@
 #if defined(ENABLE_NOTIFICATIONS)
 #include "chrome/browser/notifications/notifier_state_tracker.h"
 #include "chrome/browser/notifications/notifier_state_tracker_factory.h"
 #include "ui/message_center/notifier_settings.h"
 #endif
 
 #if defined(OS_CHROMEOS)
 #include "chrome/browser/app_mode/app_mode_utils.h"
 #include "chrome/browser/chromeos/app_mode/kiosk_app_update_install_gate.h"
 #include "chrome/browser/chromeos/extensions/device_local_account_management_policy_provider.h"
+#include "chrome/browser/chromeos/extensions/signin_screen_policy_provider.h"
 #include "chrome/browser/chromeos/policy/device_local_account.h"
+#include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chromeos/chromeos_switches.h"
 #include "chromeos/login/login_state.h"
 #include "components/user_manager/user.h"
 #include "components/user_manager/user_manager.h"
 #endif
 
 using content::BrowserThread;
 
 namespace extensions {
 
@@ skipping 41 matching lines @@
   const user_manager::User* user =
       user_manager::UserManager::Get()->GetActiveUser();
   policy::DeviceLocalAccount::Type device_local_account_type;
   if (user &&
       policy::IsDeviceLocalAccountUser(user->GetAccountId().GetUserEmail(),
                                        &device_local_account_type)) {
     device_local_account_management_policy_provider_.reset(
         new chromeos::DeviceLocalAccountManagementPolicyProvider(
             device_local_account_type));
   }
-#endif  // defined(OS_CHROMEOS)
+// We can not perform check for Signin Profile here, as it would result in
+// recursive call upon creation of Signin Profile, so we will create
+// SigninScreenPolicyProvider lazily in RegisterManagementPolicyProviders.
+#endif
 }
 
 void ExtensionSystemImpl::Shared::RegisterManagementPolicyProviders() {
   management_policy_->RegisterProviders(
       ExtensionManagementFactory::GetForBrowserContext(profile_)
           ->GetProviders());
 
 #if defined(OS_CHROMEOS)
+  // Lazy creation of SigninScreenPolicyProvider.
+  if (!signin_screen_policy_provider_) {
+    if (profile_ ==
+        chromeos::ProfileHelper::GetSigninProfile()->GetOriginalProfile()) {

[Devlin, 2016/11/11 16:35:08]

nit: prefer Profile::IsSameProfile()

[Denis Kuznetsov (DE-MUC), 2016/11/11 21:26:34]

Acknowledged.

+      signin_screen_policy_provider_.reset(
+          new chromeos::SigninScreenPolicyProvider());
+    }
+  }
+
   if (device_local_account_management_policy_provider_) {
     management_policy_->RegisterProvider(
         device_local_account_management_policy_provider_.get());
   }
+  if (signin_screen_policy_provider_)
+    management_policy_->RegisterProvider(signin_screen_policy_provider_.get());
 #endif  // defined(OS_CHROMEOS)
 
   management_policy_->RegisterProvider(InstallVerifier::Get(profile_));
 }
 
 void ExtensionSystemImpl::Shared::InitInstallGates() {
   update_install_gate_.reset(new UpdateInstallGate(extension_service_.get()));
   extension_service_->RegisterInstallGate(
       ExtensionPrefs::DELAY_REASON_WAIT_FOR_IDLE, update_install_gate_.get());
   extension_service_->RegisterInstallGate(
@@ skipping 295 matching lines @@
 void ExtensionSystemImpl::UnregisterExtensionWithRequestContexts(
     const std::string& extension_id,
     const UnloadedExtensionInfo::Reason reason) {
   BrowserThread::PostTask(
       BrowserThread::IO,
       FROM_HERE,
       base::Bind(&InfoMap::RemoveExtension, info_map(), extension_id, reason));
 }
 
 }  // namespace extensions