expose TraceEventHelper

(cherry picked from commit 220d9622de7a81cd8d421be994fed59311c720cb)

src/tracing/trace_event.h

@@ -308,7 +308,7 @@ const int kZeroNumArgs = 0;
 const decltype(nullptr) kGlobalScope = nullptr;
 const uint64_t kNoId = 0;
 
-class TraceEventHelper {
+class NODE_EXTERN TraceEventHelper {
  public:
   static v8::TracingController* GetTracingController();
   static void SetTracingController(v8::TracingController* controller);