FRF: Wiring GC events to JFR

[Aleksey Shipilev]

On 08/24/2018 10:56 PM, Zhengyu Gu wrote:
> Shenandoah has yet to wire proper events to JFR, this patch only address GC events.
> 
> Webrev:
> http://cr.openjdk.java.net/~zgu/shenandoah/jfr-event-1/webrev.00/

Let's split the part that rewires the messages and the part that binds JFR.

Thanks,
-Aleksey