[8u] Shenandoah: hook statistics printing to PrintGCDetails, not PrintGC

[Aleksey Shipilev]

Hi,

Current 8u hooks up statistics printing to PrintGC, which outputs them with -verbose:gc. Should be 
PrintGCDetails, so that is not printed by default, but only on request.

Fix:

diff -r 303c0feef063 src/share/vm/gc_implementation/shenandoah/shenandoahControlThread.cpp
--- a/src/share/vm/gc_implementation/shenandoah/shenandoahControlThread.cpp     Thu Aug 20 09:33:06 
2020 +0200
+++ b/src/share/vm/gc_implementation/shenandoah/shenandoahControlThread.cpp     Thu Aug 20 10:55:02 
2020 +0200
@@ -281,11 +281,11 @@
        if (ShenandoahPacing) {
          heap->pacer()->flush_stats_to_cycle();
        }

        // Print GC stats for current cycle
-      if (PrintGC) {
+      if (PrintGCDetails) {
          ResourceMark rm;
          heap->phase_timings()->print_cycle_on(gclog_or_tty);
          if (ShenandoahPacing) {
            heap->pacer()->print_cycle_on(gclog_or_tty);
          }

Testing: adhoc runs with {-verbose:gc, -XX:+PrintGCDetails}

-- 
Thanks,
-Aleksey