[10] RFR(M) 8182701: Modify JVMCI to allow Graal Compiler to expose platform MBean

[Vladimir Kozlov]

https://bugs.openjdk.java.net/browse/JDK-8182701
webrev:
http://cr.openjdk.java.net/~kvn/8182701/webrev.jdk/
http://cr.openjdk.java.net/~kvn/8182701/webrev.hs/

Contributed by Jaroslav Tulach.

JDK itself contains quite a lot of platform MBeans which get registered "on demand". Graal compiler (jdk.internal.vm.compiler) provides its own MBean(s) - however currently there is no way to register 
it "on demand". JDK9 already contains support for collecting platform MBeans from various modules. We just need to expose Graal MBean through JVMCI.

Thanks,
Vladimir