getDashManifest = (url, options) => new Promise((resolve, reject) => {
  let formats = {};
  const parser = sax.parser(false);
  parser.onerror = reject;
  let adaptationSet;
  parser.onopentag = node => {
    if (node.name === 'ADAPTATIONSET') {
      adaptationSet = node.attributes;
    } else if (node.name === 'REPRESENTATION') {
      const itag = parseInt(node.attributes.ID);
      if (!isNaN(itag)) {
        formats[url] = Object.assign({
          itag, url,
          bitrate: parseInt(node.attributes.BANDWIDTH),
          mimeType: `${adaptationSet.MIMETYPE}; codecs="${node.attributes.CODECS}"`,
        }, node.attributes.HEIGHT ? {
          width: parseInt(node.attributes.WIDTH),
          height: parseInt(node.attributes.HEIGHT),
          fps: parseInt(node.attributes.FRAMERATE),
        } : {
          audioSampleRate: node.attributes.AUDIOSAMPLINGRATE,
        });
      }
    }
  };
  parser.onend = () => { resolve(formats); };
  const req = utils.exposedMiniget(new URL(url, BASE_URL).toString(), options);
  req.setEncoding('utf8');
  req.on('error', reject);
  req.on('data', chunk => { parser.write(chunk); });
  req.on('end', parser.close.bind(parser));
})
Gets additional DASH formats.

@param {string} url
@param {Object} options
@returns {Promise<Array.<Object>>}