RFR: 8223822: Add gc IDs in the log of gc verification

[Jie Fu]

Hi all,

JBS: https://bugs.openjdk.java.net/browse/JDK-8223822

Please review the following patch which improves the readability of gc 
verification log.
The change is helpful for gc analysis and debugging.
-----------------------------------
diff -r 6a60270af76b src/hotspot/share/logging/logPrefix.hpp
--- a/src/hotspot/share/logging/logPrefix.hpp   Mon May 13 20:45:03 2019 
-0700
+++ b/src/hotspot/share/logging/logPrefix.hpp   Tue May 14 13:38:11 2019 
+0800
@@ -71,6 +71,8 @@
    LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, phases, ref)) \
    LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, phases, start)) \
    LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, phases, task)) \
+  LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, phases, verify)) \
+  LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, phases, verify, start)) \
    LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, plab)) \
    LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, promotion)) \
    LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, region)) \
@@ -88,6 +90,8 @@
    LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, task, time)) \
    DEBUG_ONLY(LOG_PREFIX(Test_log_prefix_prefixer, LOG_TAGS(logging, 
test))) \
    LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, tlab)) \
+  LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, verify)) \
+  LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, verify, start)) \
    LOG_PREFIX(GCId::print_prefix, LOG_TAGS(gc, workgang))
-----------------------------------
For more info, please see the JBS.

Testing:
   - make test TEST="jtreg:hotspot_gc" CONF=release

Thanks a lot.

Best regards,
Jie