INSERT DELAYED on a Mroonga table hangs and does not honor lock_wait_timeout value

Also filed as https://github.com/mroonga/mroonga/issues/20

install plugin mroonga soname 'ha_mroonga.so';

# Initialize other Mroonga stuff if necessary

create table t1 (i int) engine=Mroonga;

lock table t1 read;

--connect (con1,localhost,root,,)

set lock_wait_timeout=1;

insert delayed into t1 values (1);

Reasonable outcomes would be:

throw an error that DELAYED option is not supported;
support the option and return from the query immediately;
ignore the option and process the statement as a normal INSERT (preferably with a warning).
Hanging is not a good option.

Observed on lp:maria/10.0 revno 4427.