message: Respect .default property of TSTypeParameter.
diff: @@ -1964,6 +1964,11 @@ function genericPrintNoParens(path, options, print) {
  path.call(print, "constraint")
  );
  }
  +
  + if (n["default"]) {
  + parts.push(" = ", path.call(print, "default"));
  + }
  +
  return concat(parts);
  }
  