code: @InterfaceAudience.Public
      public Map<String, Object> getDocumentProperties() {
          return documentRevision != null ? documentRevision.getProperties() : null;
      }
docs: The properties of the document this row was mapped from.
  To get this, you must have set the -prefetch property on the query; else this will be nil.
  The map returned is immutable (run through Collections.unmodifiableMap)