Fix refresh token is not available after Chrome restart on crash.

chrome/browser/chromeos/login/session/user_session_manager.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/chromeos/login/session/user_session_manager.h"
 
 #include <stddef.h>
 
 #include <set>
 #include <string>
@@ skipping 530 matching lines @@
   // user_id (kStubUser) and certain services like restoring OAuth session are
   // explicitly disabled for it.
   if (!user_manager->IsUserLoggedIn() ||
       !user_manager->IsLoggedInAsUserWithGaiaAccount() ||
       user_manager->IsLoggedInAsStub()) {
     return;
   }
 
   const user_manager::User* user =
       ProfileHelper::Get()->GetUserByProfile(user_profile);
+
+  const SigninManagerBase* signin_manager =
+      SigninManagerFactory::GetForProfile(user_profile);
+  if (!signin_manager || signin_manager->GetAuthenticatedAccountId().empty())
+    LOG(ERROR) << "No account is associated with sign-in manager on restore.";

[msarda, 2017/03/16 16:41:57]

Suggestion: Consider adding a UMA histogram for this to be able to monitor how
often this event occurs.

[khmel, 2017/03/16 17:06:36]

Nice point!

+
   DCHECK(user);
   if (!net::NetworkChangeNotifier::IsOffline()) {
     pending_signin_restore_sessions_.erase(user->GetAccountId().GetUserEmail());
     RestoreAuthSessionImpl(user_profile, false /* has_auth_cookies */);
   } else {
     // Even if we're online we should wait till initial
     // OnConnectionTypeChanged() call. Otherwise starting fetchers too early may
     // end up canceling all request when initial network connection type is
     // processed. See http://crbug.com/121643.
     pending_signin_restore_sessions_.insert(
@@ skipping 1353 matching lines @@
           ->browser_policy_connector_chromeos()
           ->IsEnterpriseManaged()) {
     return false;
   }
 
   // Do not show end of life notification if this is a guest session
   return !profile->IsGuestSession();
 }
 
 }  // namespace chromeos