redo log encryption fails to error out even if keyring plugin configuration is missing

• Create seed database w/o any encryption
• Start ps instance with redo log encryption (w/o specifying keyring plugin params).
• Expected: Error out as set innodb_redo_log_encrypt to 0 as done by upstream (mysql)

mysql> select @@innodb_redo_log_encrypt;
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1 row in set (0.00 sec)
2019-03-12T09:10:06.911664Z 0 [ERROR] [MY-012661] [InnoDB] Encryption can't find master key, please check the keyring plugin is loaded.
2019-03-12T09:10:06.911718Z 0 [ERROR] [MY-013068] [InnoDB] Can't set redo log tablespace to be encrypted.

• PS allows the server to boot doesn't throw any error and doesn't even set innodb_redo_log_encrypt = 0. This is not true since w/o keyring how can PS encrypt the said redo log space. Where does it store/caches the key.
• Now if we specify innodb_log_file_size=XM (something > default) that would cause the creation of InnoDB log file this would error out but the default file doesn't.