message: Printer case for Flow BigIntTypeAnnotation.
diff: @@ -1798,6 +1798,9 @@ function genericPrintNoParens(path: any, options: any, print: any) {
  case "SymbolTypeAnnotation":
  return fromString("symbol", options);
  + case "BigIntTypeAnnotation":
  + return fromString("bigint", options);
  +
  // Type Annotations for TypeScript (when using Babylon as parser)
  case "TSType":
  throw new Error("unprintable type: " + JSON.stringify(n.type));
  