Re: [whatwg/dom] Allow for filtering events in "once" handlers (#990)

Example using abort controllers:

```js
const controller = new AbortController();
const { signal } = controller;

someElement.addEventListener('keypress', (event) => {
  if (event.key !== 'Escape') return;
  controller.abort();
  // Process the event
}, { signal });
```

I don't think any of the proposed shorthands help here.

I agree that `once` isn't particularly useful. `eventFilter` is interesting and makes it a bit more useful, but it doesn't help the case where you're waiting for one of multiple events:

```js
const controller = new AbortController();
const { signal } = controller;

thing.addEventListener('load', (event) => {
  controller.abort();
  // …
}, { signal });

thing.addEventListener('error', (event) => {
  controller.abort();
  // …
}, { signal });
```

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