Re: [web-nfc] add a cancelAll() instead of cancelPush()

If we have "any" we can declare cancellation method as:
```javascript
Promise<void> cancelPush(NFCPushTarget target = "any");
```
@kenchris 
cancelAll - also cancels watches? :smile: 
I checked cancellable promises repo, I'm not sure how it will work for
 async operations that require UA to interact with underlying HW. 
Cancel would need to return another promise.

E.g. push().cancel().then(cancelled, cannot_cancel);
Another issue is that how do you cancel this: 
navigator.nfc.push().then();
Developers would need to cache returned promises everywhere, so that 
they can cancel unresolved promise when needed.


-- 
GitHub Notif of comment by alexshalamov
See https://github.com/w3c/web-nfc/issues/86#issuecomment-153361905

Received on Tuesday, 3 November 2015 13:57:21 UTC