hg: jdk/hs: 8200374: Add ThreadsSMRSupport::verify_hazard_pointer_scanned() to verify threads_do().

[daniel.daugherty at oracle.com]

Changeset: 129d60b5dac7
Author:    dcubed
Date:      2018-04-12 09:03 -0400
URL:       http://hg.openjdk.java.net/jdk/hs/rev/129d60b5dac7

8200374: Add ThreadsSMRSupport::verify_hazard_pointer_scanned() to verify threads_do().
Summary: Add verification for the threads_do() part of the Thread-SMR protocol.
Reviewed-by: eosterlund, dholmes, rehn

! src/hotspot/share/runtime/thread.cpp
! src/hotspot/share/runtime/thread.hpp
! src/hotspot/share/runtime/threadSMR.cpp
! src/hotspot/share/runtime/threadSMR.hpp
+ src/hotspot/share/trace/tracingExport.cpp
+ src/hotspot/share/trace/tracingExport.hpp