Calling a generator function returns a generator object

src/heap.cc

Index: src/heap.cc
diff --git a/src/heap.cc b/src/heap.cc
index 76f0a3c9a86e052add7782f4600217d317fc5a44..a01a8b2c3aaffc4ce8c04c9231987b42e5517e91 100644
--- a/src/heap.cc
+++ b/src/heap.cc
@@ -4089,9 +4089,8 @@ MaybeObject* Heap::AllocateInitialMap(JSFunction* fun) {
   int instance_size;
   int in_object_properties;
   if (fun->shared()->is_generator()) {
-    // TODO(wingo): Replace with JS_GENERATOR_OBJECT_TYPE.
-    instance_type = JS_OBJECT_TYPE;
-    instance_size = JSObject::kHeaderSize;
+    instance_type = JS_GENERATOR_OBJECT_TYPE;
+    instance_size = JSGeneratorObject::kSize;
     in_object_properties = 0;
   } else {
     instance_type = JS_OBJECT_TYPE;