RequestTrailerMap& FilterManager::addDecodedTrailers() {
  // Trailers can only be added during the last data frame (i.e. end_stream = true).
  ASSERT(state_.filter_call_state_ & FilterCallState::LastDataFrame);

  filter_manager_callbacks_.setRequestTrailers(RequestTrailerMapImpl::create());
  return *filter_manager_callbacks_.requestTrailers();
}
RequestTrailerMap& FilterManager::addDecodedTrailers() {
   
  ASSERT(state_.filter_call_state_ & FilterCallState::LastDataFrame);

  filter_manager_callbacks_.setRequestTrailers(RequestTrailerMapImpl::create());
  return *filter_manager_callbacks_.requestTrailers();
}