Insert ephemeral IDs + correct pipeline event stats into the logstash_stats document (elastic/x-pack-elasticsearch#1747)
Insert ephemeral IDs + correct pipeline event stats into the logstash_stats document (elastic/x-pack-elasticsearch#1747)

Before the event stats were mislabeled, so were not being indexed, and
the ephemeral_id was only in the _state document.

Original commit: elastic/x-pack-elasticsearch@ca0ec81aa5e6b1085ff71d6f15267ddb58f9a7f3

vroyer/elassandra,scorpionvicky/elasticsearch,coding0011/elasticsearch,HonzaKral/elasticsearch,strapdata/elassandra,HonzaKral/elasticsearch,nknize/elasticsearch,scorpionvicky/elasticsearch,coding0011/elasticsearch,nknize/elasticsearch,vroyer/elassandra,gfyoung/elasticsearch,scorpionvicky/elasticsearch,nknize/elasticsearch,uschindler/elasticsearch,strapdata/elassandra,GlenRSmith/elasticsearch,gfyoung/elasticsearch,nknize/elasticsearch,scorpionvicky/elasticsearch,GlenRSmith/elasticsearch,gingerwizard/elasticsearch,strapdata/elassandra,HonzaKral/elasticsearch,robin13/elasticsearch,gingerwizard/elasticsearch,GlenRSmith/elasticsearch,gfyoung/elasticsearch,coding0011/elasticsearch,gingerwizard/elasticsearch,gfyoung/elasticsearch,gingerwizard/elasticsearch,vroyer/elassandra,gingerwizard/elasticsearch,uschindler/elasticsearch,uschindler/elasticsearch,robin13/elasticsearch,gingerwizard/elasticsearch,uschindler/elasticsearch,strapdata/elassandra,robin13/elasticsearch,coding0011/elasticsearch,robin13/elasticsearch,GlenRSmith/elasticsearch,HonzaKral/elasticsearch,gingerwizard/elasticsearch,robin13/elasticsearch,scorpionvicky/elasticsearch,uschindler/elasticsearch,nknize/elasticsearch,gfyoung/elasticsearch,strapdata/elassandra,coding0011/elasticsearch,GlenRSmith/elasticsearch