message: event: workaround for
  This is affecting tests, introducing flakes.
  Risk level: Low
  Testing: CI
diff: @@ -62,8 +62,12 @@ void FileEventImpl::assignEvents(uint32_t events, event_base* base) {
  events |= FileReadyType::Closed;
  }
  - ASSERT(events);
  + // TODO(htuch): this should be ASSERT(events), but
  + // https://github.com/libevent/libevent/issues/984 seems to be producing unexpected
  + // behavior. The ASSERT should be restored once this issue is resolved.
  + if (events) {
  event->cb_(events);
  + }
  },
  this);
  }
  