message: Invert the all_fields_empty flag to has_fields
  Our template engine can only check whether a flag is true (not false),
  so this change was necessary.
diff: @@ -140,7 +140,7 @@ export default class RequestLetter {
  flags = {
  erase_some: !request_object.erase_all,
  - all_fields_empty: !id_data.formatted,
  + has_fields: !!id_data.formatted,
  erase_all: request_object.erase_all,
  data_portability: request_object.data_portability,
  runs: request_object.recipient_runs ? request_object.recipient_runs.length > 0 : false
  