6981746: G1: SEGV with -XX:+TraceGen0Time

Summary: Pass correct value for length to NumberSeq constructor. Guard dereferences of "body_summary" pointer with a NULL check.
Reviewed-by: tonyp, ysr

src/share/vm/gc_implementation/g1/g1CollectorPolicy.cpp

@@ -2148,7 +2148,7 @@ void G1CollectorPolicy::print_summary(PauseSummary* summary) const {
             body_summary->get_termination_seq()
           };
           NumberSeq calc_other_times_ms(body_summary->get_parallel_seq(),
-                                        7, other_parts);
+                                        6, other_parts);
           check_other_times(2, body_summary->get_parallel_other_seq(),
                             &calc_other_times_ms);
         }
@@ -2166,6 +2166,7 @@ void G1CollectorPolicy::print_summary(PauseSummary* summary) const {
     }
     print_summary(1, "Other", summary->get_other_seq());
     {
+      if (body_summary != NULL) {
         NumberSeq calc_other_times_ms;
         if (parallel) {
           // parallel
@@ -2187,10 +2188,11 @@ void G1CollectorPolicy::print_summary(PauseSummary* summary) const {
             body_summary->get_obj_copy_seq()
           };
           calc_other_times_ms = NumberSeq(summary->get_total_seq(),
-                                        7, other_parts);
+                                                6, other_parts);
         }
         check_other_times(1,  summary->get_other_seq(), &calc_other_times_ms);
       }
+    }
   } else {
     print_indent(0);
     gclog_or_tty->print_cr("none");