[11] 2020-07-17, Bulk backports to sh/jdk11

[Roman Kennke]

This looks good to me!

Thanks,
Roman

On Fri, 2020-07-17 at 11:01 +0200, Aleksey Shipilev wrote:
> 	Error verifying signature: Cannot verify message signature:
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> https://cr.openjdk.java.net/~shade/shenandoah/backports/jdk11-20200717/webrev.01/
> 
> This backports simple fixes, mostly improvements in tests:
> 
>  [backport] 8248041: Shenandoah: pre-Full GC root updates may miss
> some roots
>  [backport] 8247860: Shenandoah: add update watermark line in rich
> assert failure message
>  [backport] 8247751: Shenandoah: options tests should run with
> smaller heaps
>  [backport] 8247754: Shenandoah: mxbeans tests can be shorter
>  [backport] 8247757: Shenandoah: split heavy tests by heuristics to
> improve parallelism
> 
> Testing: hotspot_gc_shenandoah {fastdebug,release}
>