text: Array.prototype.concatAll = function() {
    var results = [];
    this.forEach(function(subArray) {
      results.push.apply(results, subArray);
    });
  
    return results;
  };
  var listsOfItems = [
    {
      name: "list01",
      items: [
        {
          "id": 1,
          "title": "a",
          "subitems": [{ id: 301, time: 70 }]
        },
        {
          "id": 2,
          "title": "b",
          "subitems": [{ id: 401, time: 30 }]
        },
      ]
    },
    {
      name: "list02",
      items: [
        {
          "id": 5,
          "title": "e",
          "subitems": [{ id: 101, time: 50 }, { id: 102, time: 40 }]
        },
        {
          "id": 7,
          "title": "f",
          "subitems": [{ id: 201, time: 10 }]
        },
      ]
    }
  ];
  var result = listsOfItems.map( (list) =>
    list.items.map( (e) =>
      e.subitems.filter( (s) =>
        s.time > 20
      ).map( (s) =>
        ({id: e.id, s: s.time})
      )
    ).concatAll()
  ).concatAll();
  console.log(result);
  // [ { id: 1, s: 70 }, { id: 2, s: 30 }, { id: 5, s: 50 }, { id: 5, s: 40 } ]
  