Collapsing Inner hits "from:1" issue

examplequeries.txt

// Test for PR 22337
// This only fails if number_of_shards ==1

DELETE test
PUT test
{
  "settings":{
      "number_of_shards": 1
  },
  "mappings": {
    "article": {
      "properties": {
        "domain": {
          "type": "keyword"
        },        
        "tweets": {
          "type": "integer"
        },           
        "title": {
          "type": "text"
        }
      }
    }
  }
}

POST test/article
{
    "domain":"site1",
    "tweets":10,
    "title":"story 1"
}
POST test/article
{
    "domain":"site1",
    "tweets":20,
    "title":"story 2"
}
POST test/article
{
    "domain":"site1",
    "tweets":30,
    "title":"story 3"
}
POST test/article
{
    "domain":"site2",
    "tweets":20,
    "title":"story 4"
}

// This use of "from" does not de-dup as expected - first inner same as root
GET test/article/_search?q=story
{
   "collapse": {
      "field": "domain",
      "inner_hits": {
         "name": "collapsed_hits",
         "size": 3,
         "from":1
      }
   }
}