[9] RFR JDK-8141618: Change JVMCI compilerToVM constant pool tests to support CP caching

[Konstantin Shefov]

Hello

Please review a test enhancement.
It is an improvement for JVMCI CompilerToVM class tests.

See https://bugs.openjdk.java.net/browse/JDK-8138708 for more info.

Bug: https://bugs.openjdk.java.net/browse/JDK-8141618
Webrev: http://cr.openjdk.java.net/~kshefov/8141618/webrev.00/

Thanks
-Konstantin