Function wrapper

test/form/samples/supports-core-js/_expected.js:16895–16899

(init)

	var InternalWeakMap;

	var wrapper = function (init) {
	  return function WeakMap() {
	    return init(this, arguments.length ? arguments[0] : undefined);
	  };
	};

	// `WeakMap` constructor
	// https://tc39.es/ecma262/#sec-weakmap-constructor