8257967: JFR: Events for loaded agents

Reviewed-by: dholmes, sspitsyn

src/hotspot/share/runtime/java.cpp

@@ -54,6 +54,7 @@
 #include "oops/objArrayOop.hpp"
 #include "oops/oop.inline.hpp"
 #include "oops/symbol.hpp"
+#include "prims/jvmtiAgentList.hpp"
 #include "prims/jvmtiExport.hpp"
 #include "runtime/continuation.hpp"
 #include "runtime/deoptimization.hpp"
@@ -516,7 +517,7 @@ void before_exit(JavaThread* thread, bool halt) {
   // Always call even when there are not JVMTI environments yet, since environments
   // may be attached late and JVMTI must track phases of VM execution
   JvmtiExport::post_vm_death();
-  Threads::shutdown_vm_agents();
+  JvmtiAgentList::unload_agents();
 
   // Terminate the signal thread
   // Note: we don't wait until it actually dies.