code: public JsonWriter jsonValue(String value) throws IOException {
      if (value == null) {
        return nullValue();
      }
      writeDeferredName();
      beforeValue();
      out.append(value);
      return this;
    }
docs: Writes {@code value} directly to the writer without quoting or
  escaping.
  
  @param value the literal string value, or null to encode a null literal.
  @return this writer.