parent child facet using scope

empty facet when specified on the child property

curl -X POST "http://localhost:9200/myindex/ParentType/_search?pretty=true" -d '
  {
    "query": {
    "has_child" : {
        "_scope" : "myscope",
        "type" : "ChildType",
        "query" : {
            "match_all" : {}
        }
    }
    },
    "facets" : {
       "scope" : "myscope",
      "title" : { "terms" : {"field" : "title"} }
    }
  }
'

facet returning results but it shouldn't when defined on the parent titles property

curl -X POST "http://localhost:9200/myindex/ParentType/_search?pretty=true" -d '
  {
    "query": {
    "has_child" : {
        "_scope" : "myscope",
        "type" : "ChildType",
        "query" : {
            "match_all" : {}
        }
    }
    },
    "facets" : {
       "scope" : "myscope",
      "titles" : { "terms" : {"field" : "titles"} }
    }
  }
'

Mappings

{
    "ParentType": {
        "properties": {
            "titles": {
                "type": "string",
                "index": "not_analyzed"
            },
            "version": {
                "type": "integer"
            }
        }
    }
}

--------------------------------------------------------------------------------
{
    "ChildType": {
        "_parent": {
            "type": "ParentType"
        },
        "_routing": {
            "required": true
        },
        "properties": {
            "title": {
                "type": "string",
                "index": "not_analyzed"
            }
        }
    }
}