RFR(XS): 8224573: Fix windows build after JDK-8221507

[Aleksey Shipilev]

On 5/22/19 8:47 AM, Langer, Christoph wrote:
> Bug: https://bugs.openjdk.java.net/browse/JDK-8224573
> Webrev: http://cr.openjdk.java.net/~clanger/webrevs/8224573.0/

Argh. Casting to unsigned is fine for now. The patch is good and trivial.

I would really like to see the types in events match those passed in to event, if possible. Ken,
please see to rectify that in the follow up patch?

-Aleksey