message: Make SSSS migration toast dismissable
diff: @@ -157,6 +157,11 @@ export default class DeviceListener {
  }
  return;
  } else if (await cli.secretStorageKeyNeedsUpgrade()) {
  + if (this._dismissedThisDeviceToast) {
  + ToastStore.sharedInstance().dismissToast(THIS_DEVICE_TOAST_KEY);
  + return;
  + }
  +
  // FIXME: do we a different message?
  ToastStore.sharedInstance().addOrReplaceToast({
  key: THIS_DEVICE_TOAST_KEY,
  