Use EmbedderHeapTracer instead of object grouping when trace_embedder_heap flag is set

src/heap/heap.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/heap/heap.h"
 
 #include "src/accessors.h"
 #include "src/api.h"
 #include "src/ast/scopeinfo.h"
 #include "src/base/bits.h"
@@ skipping 1539 matching lines @@
   return heap->InNewSpace(*p) &&
          !HeapObject::cast(*p)->map_word().IsForwardingAddress();
 }
 
 
 static bool IsUnmodifiedHeapObject(Object** p) {
   Object* 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();
 }
 
 
 void PromotionQueue::Initialize() {
   // The last to-space page may be used for promotion queue. On promotion
   // conflict, we use the emergency stack.
   DCHECK((Page::kPageSize - MemoryChunk::kBodyOffset) % (2 * kPointerSize) ==
          0);
   front_ = rear_ =
       reinterpret_cast<struct Entry*>(heap_->new_space()->ToSpaceEnd());
@@ skipping 4905 matching lines @@
 }
 
 
 // static
 int Heap::GetStaticVisitorIdForMap(Map* map) {
   return StaticVisitorBase::GetVisitorId(map);
 }
 
 }  // namespace internal
 }  // namespace v8