RFR: Upstream merge jdk/jdk11 -> shenandoah/jdk11 (tag jdk-11+28)

[Aleksey Shipilev]

On 08/22/2018 11:39 PM, Roman Kennke wrote:
> tag jdk-11+28 arrived. Let's merge it into shenandoah/jdk11
> 
> No conflicts, very few actual changes:
> 
> http://cr.openjdk.java.net/~rkennke/jdk11-upstream-merge-2018-08-22/outgoing.txt

OK! Please push ASAP.

-Aleksey