[рони]

quikki,

<script>
  var objNew = {
    text: {
        subText: {
            value: 'value1'
        },
        modificator: {
            name: 'name1',
            params: 'params1'
        }
    },
    attrs: {
        title: 'title1'
    }
};
function fn(a) {
    //a = {...a}
    for (var b in a) {
        var c = a[b];
        if ("object" == typeof c) {
            var e = !0;
            Object.keys(c).forEach(function(d) {
                a[b + "." + d] = c[d]
            });
            delete a[b]
        }
    }
    return e ? fn(a) : a
};
var obj = fn(objNew);
document.write(JSON.stringify(obj, null, 4))
  </script>