Represents a row of a report.

NOTE: The [ReportRow](https://developers.google.com/google-ads/scripts/docs/reference/adsapp/adsapp_reportrow) works as an
associative array indexed by GAQL column name.

Typical usage:

```
  var rows = report.rows();
  while (rows.hasNext()) {
    var row = rows.next();
    // The row works as an associative array
    var clicks = row['metrics.clicks'];
  }
```