message: pass text/plain data to sendBeacon
diff: @@ -443,8 +443,12 @@ module Microsoft.ApplicationInsights {
  var url = this._config.endpointUrl();
  var batch = this._buffer.batchPayloads(payload);
  + // Chrome only allows CORS-safelisted values for the sendBeacon data argument
  + // see: https://bugs.chromium.org/p/chromium/issues/detail?id=720283
  + let plainTextBatch = new Blob([batch], { type: 'text/plain;charset=UTF-8' });
  +
  // The sendBeacon method returns true if the user agent is able to successfully queue the data for transfer. Otherwise it returns false.
  - var queued = (<any>navigator).sendBeacon(url, batch);
  + var queued = navigator.sendBeacon(url, plainTextBatch);
  if (queued) {
  this._buffer.markAsSent(payload);
  