Use EmbedderHeapTracer instead of object grouping when trace_embedder_heap flag is set

src/heap/heap.cc

Index: src/heap/heap.cc
diff --git a/src/heap/heap.cc b/src/heap/heap.cc
index ce92611c0755c8d0530a45f1b6d0a8c86ac2f9fd..d4353cefb6da5c8b70755c73aeb4bae063061b2a 100644
--- a/src/heap/heap.cc
+++ b/src/heap/heap.cc
@@ -115,7 +115,6 @@ Heap::Heap()
       inline_allocation_disabled_(false),
       total_regexp_code_generated_(0),
       tracer_(nullptr),
-      embedder_heap_tracer_(nullptr),
       high_survival_rate_period_length_(0),
       promoted_objects_size_(0),
       promotion_ratio_(0),
@@ -1554,15 +1553,12 @@ static bool IsUnmodifiedHeapObject(Object** p) {
   if (object->IsSmi()) return false;
   HeapObject* heap_object = HeapObject::cast(object);
   if (!object->IsJSObject()) return false;
-  Object* obj_constructor = (JSObject::cast(object))->map()->GetConstructor();
-  if (!obj_constructor->IsJSFunction()) return false;
-  JSFunction* constructor = JSFunction::cast(obj_constructor);
-  if (!constructor->shared()->IsApiFunction()) return false;
-  if (constructor != nullptr &&
-      constructor->initial_map() == heap_object->map()) {
-    return true;
-  }
-  return false;
+  JSObject* js_object = JSObject::cast(object);
+  if (!js_object->WasConstructedFromApiFunction()) return false;
+  JSFunction* constructor =
+      JSFunction::cast(js_object->map()->GetConstructor());
+
+  return constructor->initial_map() == heap_object->map();
 }
 
 
@@ -3589,6 +3585,7 @@ AllocationResult Heap::CopyJSObject(JSObject* source, AllocationSite* site) {
   CHECK(map->instance_type() == JS_REGEXP_TYPE ||
         map->instance_type() == JS_OBJECT_TYPE ||
         map->instance_type() == JS_ARRAY_TYPE ||
+        map->instance_type() == JS_API_OBJECT_TYPE ||
         map->instance_type() == JS_SPECIAL_API_OBJECT_TYPE);
 
   int object_size = map->instance_size();
@@ -5385,6 +5382,26 @@ void Heap::NotifyDeserializationComplete() {
 #endif  // DEBUG
 }
 
+void Heap::SetEmbedderHeapTracer(EmbedderHeapTracer* tracer) {
+  mark_compact_collector()->SetEmbedderHeapTracer(tracer);
+}
+
+bool Heap::UsingEmbedderHeapTracer() {
+  return mark_compact_collector()->embedder_heap_tracer();
+}
+
+void Heap::TracePossibleWrapper(JSObject* js_object) {
+  DCHECK(js_object->WasConstructedFromApiFunction());
+  if (js_object->GetInternalFieldCount() >= 2 &&
+      js_object->GetInternalField(0) != undefined_value() &&
+      js_object->GetInternalField(1) != undefined_value()) {
+    mark_compact_collector()->wrappers_to_trace().push_back(
+        std::pair<void*, void*>(
+            reinterpret_cast<void*>(js_object->GetInternalField(0)),
+            reinterpret_cast<void*>(js_object->GetInternalField(1))));
+  }
+}
+
 void Heap::RegisterExternallyReferencedObject(Object** object) {
   DCHECK(mark_compact_collector()->in_use());
   HeapObject* heap_object = HeapObject::cast(*object);
@@ -5560,12 +5577,6 @@ void Heap::RemoveGCEpilogueCallback(v8::Isolate::GCCallback callback) {
   UNREACHABLE();
 }
 
-void Heap::SetEmbedderHeapTracer(EmbedderHeapTracer* tracer) {
-  DCHECK_NOT_NULL(tracer);
-  CHECK_NULL(embedder_heap_tracer_);
-  embedder_heap_tracer_ = tracer;
-}
-
 // TODO(ishell): Find a better place for this.
 void Heap::AddWeakObjectToCodeDependency(Handle<HeapObject> obj,
                                          Handle<DependentCode> dep) {