function getMetadataResource(that, quadKey, version, request) {
  return that._resource.getDerivedResource({
    url: `flatfile?q2-0${quadKey}-q.${version.toString()}`,
    request: request,
  });
}
Gets information about a tile from a quadKey

@param {string} quadkey The quadkey for the tile
@returns {GoogleEarthEnterpriseTileInformation|undefined} Information about the tile or undefined if it isn't loaded.

@private