Summary: Don't post information which uses metadata from unloaded nmethods
Tested tier1-3 and 100 times with test that failed (reproduced failure without the fix).
open webrev at http://cr.openjdk.java.net/~coleenp/2019/8173361.01/webrev bug link https://bugs.openjdk.java.net/browse/JDK-8173361 Thanks, Coleen
