Issue #2504849 by Berdir, catch, alexpott: User::getAnonymousUser() takes 13ms...

Issue #2504849 by Berdir, catch, alexpott: User::getAnonymousUser() takes 13ms due to ContentEntityBase::setDefaultLangcode()

core/modules/user/src/Entity/User.php

@@ -416,6 +416,9 @@ public static function getAnonymousUser() {
       static::$anonymousUser = new $class([
         'uid' => [LanguageInterface::LANGCODE_DEFAULT => 0],
         'name' => [LanguageInterface::LANGCODE_DEFAULT => ''],
+        // Explicitly set the langcode to ensure that field definitions do not
+        // need to be fetched to figure out a default.
+        'langcode' => [LanguageInterface::LANGCODE_DEFAULT => LanguageInterface::LANGCODE_NOT_SPECIFIED]
       ], $entity_type->id());
     }
     return clone static::$anonymousUser;