RFR: 8214295: Populate handlers while holding streamHandlerLock

[Chris Hegarty]

On 26/11/2018 12:12, Seán Coffey wrote:
> JDK-8213942 synchronization fix can be improved. Details in bug report.
> 
> https://bugs.openjdk.java.net/browse/JDK-8214295
> 
> http://cr.openjdk.java.net/~coffeys/webrev.8214295/webrev/

LGTM.

-Chris.