cluster: add handle ref/unref stubs in rr mode
Add ref() and unref() stub methods to the faux handle in round-robin
mode. Fixes the following TypeError when calling server.unref()
in
the worker:
net.js:1521
this._handle.unref();
^
TypeError: this._handle.unref is not a function
at Server.unref (net.js:1521:18)
No actual reference counting is implemented. It would effectively be a no-op because the control channel would still keep the worker alive.
Fixes: https://github.com/nodejs/node/issues/73
CI: https://jenkins-iojs.nodesource.com/job/node-test-pull-request/24/