ChromeOS: should send old user GAPS cookie to GAIA on user reauthentication.

chrome/browser/chromeos/login/existing_user_controller.cc

Index: chrome/browser/chromeos/login/existing_user_controller.cc
diff --git a/chrome/browser/chromeos/login/existing_user_controller.cc b/chrome/browser/chromeos/login/existing_user_controller.cc
index 9866456dd4e0d92c43499d2566ea2e3edf68635e..b74eb3b751e9f898533323681608c8fd1bd61e52 100644
--- a/chrome/browser/chromeos/login/existing_user_controller.cc
+++ b/chrome/browser/chromeos/login/existing_user_controller.cc
@@ -1134,6 +1134,12 @@ void ExistingUserController::DoCompleteLogin(
   }
   user_context.SetDeviceId(device_id);
 
+  const std::string& gaps_cookie = user_context.GetGAPSCookie();
+  if (!gaps_cookie.empty()) {
+    user_manager::UserManager::Get()->SetKnownUserGAPSCookie(
+        user_context.GetUserID(), gaps_cookie);
+  }
+
   PerformPreLoginActions(user_context);
 
   if (!time_init_.is_null()) {