Use EmbedderHeapTracer instead of object grouping when trace_embedder_heap flag is set

include/v8.h

Index: include/v8.h
diff --git a/include/v8.h b/include/v8.h
index 0efc8f6384816d67e7a3cd1ae6e2468bfa7dafa5..71b2d060022f63aaaebb05857b5f231226e9ce4c 100644
--- a/include/v8.h
+++ b/include/v8.h
@@ -600,7 +600,7 @@ template <class T> class PersistentBase {
    * is alive. Only allowed when the embedder is asked to trace its heap by
    * EmbedderHeapTracer.
    */
-  V8_INLINE void RegisterExternalReference(Isolate* isolate);
+  V8_INLINE void RegisterExternalReference(Isolate* isolate) const;
 
   /**
    * Marks the reference to this object independent. Garbage collector is free
@@ -7353,7 +7353,8 @@ class Internals {
   static const int kNodeIsPartiallyDependentShift = 4;
   static const int kNodeIsActiveShift = 4;
 
-  static const int kJSObjectType = 0xb6;
+  static const int kJSObjectType = 0xb7;
+  static const int kJSApiObjectType = 0xb6;
   static const int kFirstNonstringType = 0x80;
   static const int kOddballType = 0x83;
   static const int kForeignType = 0x87;
@@ -7658,7 +7659,7 @@ P* PersistentBase<T>::ClearWeak() {
 }
 
 template <class T>
-void PersistentBase<T>::RegisterExternalReference(Isolate* isolate) {
+void PersistentBase<T>::RegisterExternalReference(Isolate* isolate) const {
   if (IsEmpty()) return;
   V8::RegisterExternallyReferencedObject(
       reinterpret_cast<internal::Object**>(this->val_),
@@ -7985,7 +7986,9 @@ Local<Value> Object::GetInternalField(int index) {
   O* obj = *reinterpret_cast<O**>(this);
   // Fast path: If the object is a plain JSObject, which is the common case, we
   // know where to find the internal fields and can return the value directly.
-  if (I::GetInstanceType(obj) == I::kJSObjectType) {
+  auto instance_type = I::GetInstanceType(obj);
+  if (instance_type == I::kJSObjectType ||
+      instance_type == I::kJSApiObjectType) {
     int offset = I::kJSObjectHeaderSize + (internal::kApiPointerSize * index);
     O* value = I::ReadField<O*>(obj, offset);
     O** result = HandleScope::CreateHandle(reinterpret_cast<HO*>(obj), value);
@@ -8003,7 +8006,9 @@ void* Object::GetAlignedPointerFromInternalField(int index) {
   O* obj = *reinterpret_cast<O**>(this);
   // Fast path: If the object is a plain JSObject, which is the common case, we
   // know where to find the internal fields and can return the value directly.
-  if (V8_LIKELY(I::GetInstanceType(obj) == I::kJSObjectType)) {
+  auto instance_type = I::GetInstanceType(obj);
+  if (V8_LIKELY(instance_type == I::kJSObjectType ||
+                instance_type == I::kJSApiObjectType)) {
     int offset = I::kJSObjectHeaderSize + (internal::kApiPointerSize * index);
     return I::ReadField<void*>(obj, offset);
   }