code: @Override
      public D newDocument(String id, int expiry, T content, long cas, MutationToken mutationToken) {
          LOGGER.warn("This transcoder ({}) does not support mutation tokens - this method is a " +
              "stub and needs to be implemented on custom transcoders.", this.getClass().getSimpleName());
          return newDocument(id, expiry, content, cas);
      }
docs: Default implementation for backwards compatibility.