[15] RFR(S) 8238758: [JVMCI] fix JVMCI jtreg events tests to work with GraalVM

[Dean Long]

Looks good.

dl

On 2/13/20 12:36 PM, Vladimir Kozlov wrote:
> https://bugs.openjdk.java.net/browse/JDK-8238758
> http://cr.openjdk.java.net/~kvn/8238758/webrev.00/
>
> For JVMCI testing we sometimes use dummy compiler: 
> -Djvmci.Compiler=EmptyCompiler
> It does not work correctly when libgraal (in GraalVM) is used by default.
> We have to explicitly disable libgraal use in such cases.
>
> The fix is contributed by Doug and reviewed by GraalVM group and me 
> for the fix in Graal repo.
>
> Tested with hs-tier1 when JVMCI tests run.
>
> Thanks,
> Vladimir