Related issue: https://github.com/denoland/deno/issues/19358.
This is a regression that seems to have been introduced in
https://github.com/denoland/deno/pull/18905. It looks to have been a
performance optimization.
The issue is probably easiest described with some code:
```ts
const target = new EventTarget();
const event = new Event("foo");
target.addEventListener("foo", () => {
console.log('base');
target.addEventListener("foo", () => {
console.log('nested');
});
});
target.dispatchEvent(event);
```
Essentially, the second event listener is being attached while the `foo`
event is still being dispatched. It should then not fire that second
event listener, but Deno currently does.
This commit adds brand checking to EventTarget. It also fixes a
bug where deno would crash if an abort signal was aborted on the
global addEventListener().
