With Typescript 4, `ts.updateIdentifier` is no longer available.
Calling `ts.updateIdentifier` used to return the same node when
`typeArguments` was `undefined` because `node.typeArguments`
was also `undefined`.
Relevant TS code:
```js
function updateIdentifier(node, typeArguments) {
return node.typeArguments !== typeArguments
? updateNode(createIdentifier(ts.idText(node), typeArguments), node)
: node;
}
```
PR Close#38076
281b647f15