domain: do not import util for a simple type check
This removes require('util')
from the domain
module. There was
only a single simple type check used from the util
module which
is now inlined instead.
Checklist
-
make -j4 test
(UNIX), orvcbuild test
(Windows) passes -
tests and/or benchmarks are included -
documentation is changed or added -
commit message follows commit guidelines