This commit updates the implementation of the `fetch` patch and additionally
patches `Response` methods which return promises. These are `arrayBuffer`, `blob`,
`formData`, `json` and `text`. This fixes the issue when zone becomes stable too early
before all of the `fetch` tasks complete. Given the following code:
```ts
appRef.isStable.subscribe(console.log);
fetch(...).then(response => response.json()).then(console.log);
```
The `isStable` observer would log `false, true, false, true`. This was happening because
`json()` was returning a native promise (and not a `ZoneAwarePromise`). But calling `then`
on the native promise returns a `ZoneAwarePromise` which notifies Angular about the task
being scheduled and forces to re-calculate the `isStable` state.
Issue: #50327
PR Close#50653
fetch support AbortSignal, zone.js schedules a macroTask when fetch()
```
fetch(..., {signal: abortSignal});
```
we should also be able to cancel fetch with `zoneTask.cancel` call.
So this commit create an internal AbortSignal to handle
`zoneTask.cancel()` call and also delegate the `options.signal` from the
user code.
PR Close#49595
Close#49591
```
const ac = new AbortController();
addEventListener(eventName, handler, {signal: ac.signal);`
ac.abort();
```
Currently `zone.js` doesn't support the `signal` option, this PR allows
the user to use AbortContoller to remove the event listener.
PR Close#49595
