[ignition] Optimize JSGenerator creation

src/builtins/builtins-definitions.h

Index: src/builtins/builtins-definitions.h
diff --git a/src/builtins/builtins-definitions.h b/src/builtins/builtins-definitions.h
index 18d1ac11cb8c5df6540e00101d4eb1bb3510c3ac..15f6e9ed3039ccd00b60805c794616aee2347b67 100644
--- a/src/builtins/builtins-definitions.h
+++ b/src/builtins/builtins-definitions.h
@@ -493,6 +493,7 @@ namespace internal {
   TFS(CreateIterResultObject, kValue, kDone)                                   \
                                                                                \
   /* Generator and Async */                                                    \
+  TFS(CreateGeneratorObject, kClosure, kReceiver)                              \
   CPP(GeneratorFunctionConstructor)                                            \
   /* ES6 #sec-generator.prototype.next */                                      \
   TFJ(GeneratorPrototypeNext, 1, kValue)                                       \