How to use the stacktrace-js.get function in stacktrace-js

private async mkMessage(severity: string, msg: string): Promise {
    const trace = await StackTrace.get()
    // Shift off the generated promise wrappers.
    for (let i = 0; i < 11; i++) {
      if (trace[0].fileName.match(/.*(main|zone)\.js$/) ||
          trace[0].fileName.match(/.*\/node_modules\/.*/)) {
        trace.shift();
      } else {
        break;
      }
    }

    const fn = trace[0].fileName.replace('webpack://', '');
    const message = new LogMessage(
        severity, msg,
        `${trace[0].functionName} (${fn}:${trace[0].lineNumber})`, trace);
    this.messages.push(message);
    this.messagesSubject.next(this.messages);

$window.addEventListener('AngularContextException', function(e) {
              rendering = true;
              StackTrace.get()
                  .then(function(stack){
                    c_window.console.log('StackTrace.get', stack);
                  })
                  .catch(function(err){
                    c_window.console.log('StackTrace.catch', err);
                  });
              c_window.cacheEngine.removeCache(url);
              c_window.console.error("AngularContextException caught on server");
              c_window.console.error(e);
              utils.closeSession(c_window, window);
              res.end('SERVER-ERROR');
            });

function getTrace(conf: _Conf, cb: (StackFrame[]) => mixed) {
  if (conf.stackTrace.length) {
    if (conf.stackTraceAsync) {
      Stacktrace.get().then(xs => setTimeout(() => cb(xs), 0));
    } else {
      cb(Stacktrace.getSync());
    }
  } else {
    cb([]);
  }
}