Tested in Rx.Net.

```C#
            var o = Observable.Create<int>(observer => {
                observer.OnNext(2);
                Thread.Sleep(2000);
                observer.OnError(new Exception("test"));
                return Disposable.Empty;
            });
            o.SkipLast(TimeSpan.FromMilliseconds(100)).ObserveOn(Scheduler.NewThread).Subscribe(
                next=>Console.WriteLine(next),
                e => Console.WriteLine(e),
                () => Console.WriteLine("onCompleted")
                );
            Console.ReadLine();
```
The above codes only output
```
System.Exception: test
```

So Rx.Net only emits `onError` and drops the buffer?