RFR: Disable ShenandoahCompileCheck by default

[Roman Kennke]

ok. (for now)

Roman

> There seem to be upstream compiler errors [1] that make our nightlies unhappy with
> ShenandoahCompileCheck begin trueInDebug. Let's demote it to false:
> 
> diff -r 35f51ec57ad7 src/hotspot/share/gc/shenandoah/shenandoah_globals.hpp
> --- a/src/hotspot/share/gc/shenandoah/shenandoah_globals.hpp    Mon Aug 06 16:49:07 2018 +0200
> +++ b/src/hotspot/share/gc/shenandoah/shenandoah_globals.hpp    Wed Aug 08 09:49:59 2018 +0200
> @@ -421,9 +421,9 @@
>            "Tracing task termination timings")                               \
>                                                                              \
>    diagnostic(bool, ShenandoahElasticTLAB, true,                             \
>            "Use Elastic TLABs with Shenandoah")                              \
>                                                                              \
> -  diagnostic(bool, ShenandoahCompileCheck, trueInDebug,                     \
> +  diagnostic(bool, ShenandoahCompileCheck, false,                           \
>            "Assert that methods are successfully compilable")                \
> 
>  #endif // SHARE_VM_GC_SHENANDOAH_SHENANDOAH_GLOBALS_HPP
> 
> Testing: tier1_gc_shenandoah
> 
> Thanks,
> -Aleksey
> 
> [1] http://mail.openjdk.java.net/pipermail/shenandoah-dev/2018-August/007023.html
>