Implement oauth token external handler checking.

chrome/browser/chromeos/login/ui/login_display_host_impl.cc

Index: chrome/browser/chromeos/login/ui/login_display_host_impl.cc
diff --git a/chrome/browser/chromeos/login/ui/login_display_host_impl.cc b/chrome/browser/chromeos/login/ui/login_display_host_impl.cc
index 38b426af97e586f92bc419fb257dfc865fae61a7..79e18d95ff4587bcf49d15e918f9e4a843bec79a 100644
--- a/chrome/browser/chromeos/login/ui/login_display_host_impl.cc
+++ b/chrome/browser/chromeos/login/ui/login_display_host_impl.cc
@@ -37,6 +37,7 @@
 #include "chrome/browser/chromeos/login/helper.h"
 #include "chrome/browser/chromeos/login/login_wizard.h"
 #include "chrome/browser/chromeos/login/screens/core_oobe_actor.h"
+#include "chrome/browser/chromeos/login/signin/token_handler_util.h"
 #include "chrome/browser/chromeos/login/startup_utils.h"
 #include "chrome/browser/chromeos/login/ui/input_events_blocker.h"
 #include "chrome/browser/chromeos/login/ui/keyboard_driven_oobe_key_handler.h"
@@ -71,6 +72,7 @@
 #include "chromeos/settings/timezone_settings.h"
 #include "chromeos/timezone/timezone_resolver.h"
 #include "components/session_manager/core/session_manager.h"
+#include "components/user_manager/user.h"
 #include "components/user_manager/user_manager.h"
 #include "content/public/browser/notification_service.h"
 #include "content/public/browser/notification_types.h"
@@ -628,6 +630,22 @@ void LoginDisplayHostImpl::StartSignInScreen(
   SetStatusAreaVisible(true);
   existing_user_controller_->Init(users);
 
+  // Validate user OAuth tokens.
+
+  if (base::CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kEnableOAuthTokenHandlers)) {
+    token_handler_util_.reset(
+        new TokenHandlerUtil(user_manager::UserManager::Get()));
+    for (auto* user : users) {
+      auto user_id = user->GetUserID();
+      if (token_handler_util_->HasToken(user_id)) {
+        token_handler_util_->CheckToken(
+            user_id, base::Bind(&LoginDisplayHostImpl::OnTokenHandlerChecked,
+                                pointer_factory_.GetWeakPtr()));
+      }
+    }
+  }
+
   // We might be here after a reboot that was triggered after OOBE was complete,
   // so check for auto-enrollment again. This might catch a cached decision from
   // a previous oobe flow, or might start a new check with the server.
@@ -654,6 +672,16 @@ void LoginDisplayHostImpl::StartSignInScreen(
       "login-wait-for-signin-state-initialize");
 }
 
+void LoginDisplayHostImpl::OnTokenHandlerChecked(
+    const user_manager::UserID& user_id,
+    TokenHandlerUtil::TokenHandleStatus token_status) {
+  if (token_status == TokenHandlerUtil::INVALID) {
+    user_manager::UserManager::Get()->SaveUserOAuthStatus(
+        user_id, user_manager::User::OAUTH2_TOKEN_STATUS_INVALID);
+    token_handler_util_->DeleteToken(user_id);
+  }
+}
+
 void LoginDisplayHostImpl::OnPreferencesChanged() {
   if (is_showing_login_)
     webui_login_display_->OnPreferencesChanged();