* volume: also listen on localhost like other components
Master, filer and s3 bind both the detected host ip and localhost via
NewIpAndLocalListeners, but the volume server used a plain NewListener on
bindIp, so a volume bound to the host ip never answers on loopback. Any
tooling that polls localhost (e.g. the java test workflow's readiness
curl on localhost:8080/status) then waits out its full timeout even
though the volume is up and registered with the master.
Use NewIpAndLocalListeners for the volume grpc, public and cluster http
listeners, and add a small multiHttpdownServer composite so graceful
shutdown still covers both listeners.
* volume: stop and wait dual listeners concurrently
A serial multiHttpdownServer.Stop let the localhost listener keep
accepting requests while the bound-ip listener drained, and a serial
Wait hid a localhost serving failure until the bound-ip listener ended.
Run both waits and both stops in parallel: Wait reports the first error
promptly, Stop closes every listener when shutdown begins.
Chris Lu
29b81a827d