RFR [11] 2018-12-05: Bulk backports to sh/jdk11

[Roman Kennke]

Looks good! Thank you!
Roman

> http://cr.openjdk.java.net/~shade/shenandoah/backports/jdk11-20181205/webrev.01/
> 
> This backports recent work to sh/jdk11. Most of that stuff is redoing copyrights, renames, moves to
> match what we did in sh/jdk for upstreaming.
> 
> Changes:
> 
>  [backport] Remove _shenandoah_partial_gc GCCause
>  [backport] Update copyrights
>  [backport] Prepare tests for upstreaming
>  [backport] Small cleanup in node.hpp
>  [backport] Minor cleanup of Shenandoah SA
>  [backport] Eliminating Shenandoah exposure to CLD
>  [backport] Use ShenandoahAllocationThreshold in ShenandoahStaticHeuristics constructor
>  [backport] Remove obsolete unused flags
>  [backport] Remove ShenandoahWriteBarrierRB flag
>  [backport] Rename ParallelSafepointCleanupThreads to ShenandoahParallelSafepointThreads
>  [backport] Rename VerifyObjectEquals to ShenandoahVerifyObjectEquals
>  [backport] Clean up and regroup Shenandoah flags
>  [backport] Shenandoah test groups should not include each other
>  [backport] Fix various formattings and namings in shared GC code
>  [backport] Shenandoah should @require Shenandoah, @key gc, and have good @test
>  [backport] remove TraceLoopPredicate change
>  [backport] Fix indentation of CriticalNative* tests
>  [backport] Fix shared tests to run without Shenandoah
>  [backport] Disable heap iteration for Shenandoah in SA
>  [backport] Filter out heap walk related hotspot_serviceability test
>  [backport] remove useless change in loopnode.cpp
>  [backport] Reformat Shenandoah tests
>  [backport] Remove obsolete and ignored TestHeapAlloc
>  [backport] Move Shenandoah tests to proper locations
>  [backport] Drop "Shenandoah" from test names
>  [backport] Prefix Shenandoah tests with "Test"
>  [backport] Rename UINT64_FORMAT_HEX_W to UINT64_FORMAT_X_W
>  [backport] Put Shenandoah configs/macros in alphabetical order
>  [backport] Move ShenandoahGCTracer to gc/shenandoah
>  [backport] Rename fields in (SA) ShenandoahHeap.java to omit 'Regions' and 'Field' suffix
>  [backport] Trim unused code from Shenandoah SA
>  [backport] Test @requires should check what GC is enabled at runtime
>  [backport] Separate "passive" heuristics from "adaptive"
>  [backport] Fail early when critical barriers are disabled
>  [backport] Reverted TestFullGCCount.java test and added comment
>  [backport] Some Shenandoah related additions to SA
>  [backport] Fix ordering of macros in vmStructs_gc.hpp and globals_gc.hpp
>  [backport] Print number of threads in Shenandoah SA heap summary
>  [backport] Re-label Shenandoah GC causes (SA&GC)
> 
> Testing: hotspot_gc_shenandoah {fastdebug|release}
> 
> Thanks,
> -Aleksey
>