nateflink/angular.js — comment on commit f9f43eabe0516a953d3d5735d713236a29cb69b1
File:  line 0
By IgorMinar:

Can you please improve this by attempting to delete first and if that throws an exception then set the property to undefined. something like:

```
try {
delete window[callbackId];
} catch() {
window[callbackId] = undefined; // IE8 and older doesn't support delete on window
}
```

Thanks!