Use EmbedderHeapTracer instead of object grouping when trace_embedder_heap flag is set

src/objects.h

Index: src/objects.h
diff --git a/src/objects.h b/src/objects.h
index e3cb08bbc47689508f96185e4729dd83531b2ab7..08260280d7520222f8f3dab5a51c940b1f33fdf4 100644
--- a/src/objects.h
+++ b/src/objects.h
@@ -420,6 +420,7 @@ const int kStubMinorKeyBits = kSmiValueSize - kStubMajorKeyBits - 1;
   V(JS_MODULE_TYPE)                                             \
   V(JS_GLOBAL_OBJECT_TYPE)                                      \
   V(JS_GLOBAL_PROXY_TYPE)                                       \
+  V(JS_API_OBJECT_TYPE)                                         \
   V(JS_SPECIAL_API_OBJECT_TYPE)                                 \
   V(JS_ARRAY_TYPE)                                              \
   V(JS_ARRAY_BUFFER_TYPE)                                       \
@@ -702,11 +703,14 @@ enum InstanceType {
   JS_PROXY_TYPE,          // FIRST_JS_RECEIVER_TYPE
   JS_GLOBAL_OBJECT_TYPE,  // FIRST_JS_OBJECT_TYPE
   JS_GLOBAL_PROXY_TYPE,
-  // Like JS_OBJECT_TYPE, but requires access checks and/or has interceptors.
+  // Like JS_API_OBJECT_TYPE, but requires access checks and/or has
+  // interceptors.
   JS_SPECIAL_API_OBJECT_TYPE,  // LAST_SPECIAL_RECEIVER_TYPE
   JS_VALUE_TYPE,               // LAST_CUSTOM_ELEMENTS_RECEIVER
   JS_MESSAGE_OBJECT_TYPE,
   JS_DATE_TYPE,
+  // Like JS_OBJECT_TYPE, but created from API function.
+  JS_API_OBJECT_TYPE,
   JS_OBJECT_TYPE,
   JS_CONTEXT_EXTENSION_OBJECT_TYPE,
   JS_GENERATOR_OBJECT_TYPE,
@@ -762,6 +766,7 @@ enum InstanceType {
 };
 
 STATIC_ASSERT(JS_OBJECT_TYPE == Internals::kJSObjectType);
+STATIC_ASSERT(JS_API_OBJECT_TYPE == Internals::kJSApiObjectType);
 STATIC_ASSERT(FIRST_NONSTRING_TYPE == Internals::kFirstNonstringType);
 STATIC_ASSERT(ODDBALL_TYPE == Internals::kOddballType);
 STATIC_ASSERT(FOREIGN_TYPE == Internals::kForeignType);
@@ -2284,6 +2289,7 @@ class JSObject: public JSReceiver {
   inline Object* GetInternalField(int index);
   inline void SetInternalField(int index, Object* value);
   inline void SetInternalField(int index, Smi* value);
+  bool WasConstructedFromApiFunction();
 
   void CollectOwnPropertyNames(KeyAccumulator* keys,
                                PropertyFilter filter = ALL_PROPERTIES);