[11u] RFR(M): 8219586 backport: CodeHeap State Analytics processes dead nmethods

[Schmidt, Lutz]

Dear Community,

I would happily accept reviews for this downport change. The change puts an end to discussions on the "accessing dead storage" topic, at least to the best of Erik Österlund's and my knowledge. 

Most merge conflicts (and the complicated ones) were encountered codeHeapState.{c|h}pp. To resolve them, I copied the files from OpenJDK/jdk. That was the desired state for these files anyway. 

To resolve compileBroker.cpp, I copied the OpenJDK/jdk version of CompileBroker::print_heapinfo() and retrofitted the Monitor and Mutex objects and calls to the jdk11 interfaces. 

The remaining conflicts were trivial to resolve.

Original bug:          https://bugs.openjdk.java.net/browse/JDK-8219586
Downport webrev:       https://cr.openjdk.java.net/~lucy/webrevs/8219586.11u.01/
Merge conflicts:       https://cr.openjdk.java.net/~lucy/webrevs/8219586-jdk11u.conflicts
Conflict resolve diff: https://cr.openjdk.java.net/~lucy/webrevs/8219586-jdk11u.conflictresolve

Tests:
SAP's internal build and test farm (all OpenJDK platforms (no 32-bit), and more). Tests include JCK, jtreg (hotspot and jdk), and SAP-private tests. Results pending (expected by April 15th, start of business).

Thanks,
Lutz