[Constructor(record<USVString, USVString> init)]
interface Foo {
  void foo(sequence<record<ByteString, any>> param);
  record<DOMString, (float or DOMString)?> bar();

  // Make sure record can still be registered as a type.
  record baz();
};

interface Bar {
  record<DOMString, [XAttr] float> bar();
};
