RFR: JMC-6206: Making the agent prototype work on OpenJDK 11

[Guru]

+1, Looks good to me. 

> On 05-Dec-2018, at 2:03 AM, Marcus Hirt <marcus at hirt.se> wrote:
> 
> Hi all,
> 
> Please review this fix to get the early agent prototype to work on OpenJDK
> 11.
> 
> Jira:  https://bugs.openjdk.java.net/browse/JMC-6206
> Patch: http://cr.openjdk.java.net/~hirt/JMC-6206/webrev.01/
> 
> Kind regards,
> Marcus
>