In order to mirror a server with per-object filtering, the client
needs to track which server callbackID is servicing the client
callback.  This patch introduces the notion of a serverID, as
well as the plumbing to use it for network events, although the
actual complexity of using per-object filtering in the remote
driver is deferred to a later patch.

* src/conf/object_event.h (virObjectEventStateEventID): Add parameter.
(virObjectEventStateQueueRemote, virObjectEventStateSetRemote):
New prototypes.
(virObjectEventStateRegisterID): Move...
* src/conf/object_event_private.h: ...here, and add parameter.
(_virObjectEvent): Add field.
* src/conf/network_event.h (virNetworkEventStateRegisterClient): New
prototype.
* src/conf/object_event.c (_virObjectEventCallback): Add field.
(virObjectEventStateSetRemote): New function.
(virObjectEventStateQueue): Make wrapper around...
(virObjectEventStateQueueRemote): New function.
(virObjectEventCallbackListCount): Tweak return count when remote
id matching is used.
(virObjectEventCallbackLookup, virObjectEventStateRegisterID):
Tweak registration when remote id matching will be used.
(virObjectEventNew): Default to no remote id.
(virObjectEventCallbackListAddID): Likewise, but set remote id
when one is available.
(virObjectEventCallbackListRemoveID)
(virObjectEventCallbackListMarkDeleteID): Adjust return value when
remote id was set.
(virObjectEventStateEventID): Query existing id.
(virObjectEventDispatchMatchCallback): Require matching event id.
(virObjectEventStateCallbackID): Adjust caller.
* src/conf/network_event.c (virNetworkEventStateRegisterClient): New
function.
(virNetworkEventStateRegisterID): Update caller.
* src/conf/domain_event.c (virDomainEventStateRegister)
(virDomainEventStateRegisterID): Update callers.
* src/remote/remote_driver.c
(remoteConnectNetworkEventRegisterAny)
(remoteConnectNetworkEventDeregisterAny)
(remoteConnectDomainEventDeregisterAny): Likewise.
(remoteEventQueue): Hoist earlier to avoid forward declaration,
and add parameter.  Adjust all callers.
* src/libvirt_private.syms (conf/object_event.h): Drop function.
Signed-off-by: NEric Blake <eblake@redhat.com>