To get rid of the need that a Worker must have an id, we store
in the MXS_POLL_DATA structure a pointer to the owning worker
instead of the id of the owning worker. This also allows some
further cleanup as the need for switching back and forth between
the id and the worker disappears.
The id will be moved from Worker to RoutingWorker as there
currently is a fair amount of code that assumes that the id of
routing workers start from 0.
This clarifies what parts of the router are specific to the binlogrouter
and what are common between the binlogrouter and avrorouter.
Ideally, the two modules would use the same infrastructure to handle the
processing of replication events. This is the first, albeit small, step
towards making the code in the binlogrouter the common infrastructure.
