RFR: 8190415: [JVMCI] JVMCIRuntime::adjust_comp_level must not swallow ThreadDeath

[Tom Rodriguez]

Looks good.

tom

Doug Simon wrote:
> Please review this change that fixes a JVMCI code path that was swallowing ThreadDeath exceptions and thus preventing Thread.stop from working as intended.
> The webrev also contains some minor unrelated cleanup to mx_jvmci.py needed for supporting the consolidated repo.
>
> The internal test that caught this problem is now passing.
>
> https://bugs.openjdk.java.net/browse/JDK-8190415
> http://cr.openjdk.java.net/~dnsimon/8190415/
>
> -Doug