Revert "[d8] cleanly force exit in d8 on windows."

src/d8.cc

Index: src/d8.cc
diff --git a/src/d8.cc b/src/d8.cc
index f6c13c755278ea59c3305069bb8aff236bc27844..80068c16f75c00acb3cb7ae6a5793513be9729b3 100644
--- a/src/d8.cc
+++ b/src/d8.cc
@@ -1625,6 +1625,16 @@ Local<Context> Shell::CreateEvaluationContext(Isolate* isolate) {
   return handle_scope.Escape(context);
 }
 
+
+void Shell::Exit(int exit_code) {
+  // Use _exit instead of exit to avoid races between isolate
+  // threads and static destructors.
+  fflush(stdout);
+  fflush(stderr);
+  _exit(exit_code);
+}
+
+
 struct CounterAndKey {
   Counter* counter;
   const char* key;