onError_(error) {
    let severity = error.severity;
    if (severity == null || error.severity == undefined) {
      // It's not a shaka.util.Error. Treat it as very severe, since those
      // should not be happening.
      severity = shaka.util.Error.Severity.CRITICAL;
    }

    const message = error.message || ('Error code ' + error.code);

    let href = '';
    if (error.code) {
      href = '../docs/api/shaka.util.Error.html#value:' + error.code;
    }

    console.error(error);
    this.handleError_(severity, message, href);
  }
@param {!shaka.util.Error} error
@private