hg: panama/dev: 8209151: StdLibTest fails intermittently

[maurizio.cimadamore at oracle.com]

Changeset: 47795e66e146
Author:    mcimadamore
Date:      2018-08-10 18:41 +0100
URL:       http://hg.openjdk.java.net/panama/dev/rev/47795e66e146

8209151: StdLibTest fails intermittently
* add lock to code cache access
* add reachability fence in NativeInvoker

! src/hotspot/cpu/x86/nativeInvoker_x86.cpp
! src/java.base/share/classes/jdk/internal/foreign/NativeInvoker.java