Binds a new worker item to this worker
Replace an existing worker item with a new one.
Replace an existing worker item with a new one. This happens, for example, as the last phase of swapping a live connection's handler. The old WorkerItem is unbound before the new one is bound. If no WorkerItem with the given id exists, the new one is not bound. This is to avoid a possible race condition that could occur if a connection is severed during the process of swapping handlers.
Returns true if the replace successfully happened, false otherwise
This keeps track of all the bound worker items, and properly handles added/removing them