MB-5311 Don't call notifyIOComplete for unreserved TAP connections
MB-5311 Don't call notifyIOComplete for unreserved TAP connections

If a given TAP connection is not reserved, this means that its
corresponding memcached connection is already in CLOSE state.
Therefore, we should not invoke notify_io_complete for those
unreserved TAP connections.

Change-Id: Ib7bb4adf3f9006d761fdd97f4996d8dd02d124e8
Reviewed-on: http://review.couchbase.org/16120
Reviewed-by: Chiyoung Seo <8b279095f11c26cc21045fda5a3e51debb005aa9@gmail.com>
Tested-by: Chiyoung Seo <8b279095f11c26cc21045fda5a3e51debb005aa9@gmail.com>
Reviewed-on: http://review.couchbase.org/16126

membase/ep-engine,sriganes/ep-engine,couchbase/ep-engine,owendCB/ep-engine,daverigby/ep-engine,jimwwalker/ep-engine,daverigby/kv_engine,daverigby/kv_engine,teligent-ru/ep-engine,hisundar/ep-engine,abhinavdangeti/ep-engine,teligent-ru/ep-engine,couchbase/ep-engine,membase/ep-engine,owendCB/ep-engine,membase/ep-engine,daverigby/ep-engine,hisundar/ep-engine,daverigby/ep-engine,abhinavdangeti/ep-engine,teligent-ru/ep-engine,teligent-ru/ep-engine,jimwwalker/ep-engine,abhinavdangeti/ep-engine,hisundar/ep-engine,membase/ep-engine,daverigby/kv_engine,daverigby/ep-engine,sriganes/ep-engine,abhinavdangeti/ep-engine,couchbase/ep-engine,sriganes/ep-engine,couchbase/ep-engine,sriganes/ep-engine,daverigby/kv_engine,abhinavdangeti/ep-engine,owendCB/ep-engine,jimwwalker/ep-engine,owendCB/ep-engine,jimwwalker/ep-engine,hisundar/ep-engine