[heap] Fix verification of unsafe object layout changes.

src/objects.h

Index: src/objects.h
diff --git a/src/objects.h b/src/objects.h
index bcb4cd49b7ddf8af12e69723e26f6cc98636fcc3..e0ebcdd53cdebcb1dff1ca6311371b51aa392285 100644
--- a/src/objects.h
+++ b/src/objects.h
@@ -1683,9 +1683,13 @@ class HeapObject: public Object {
 
   // Set the map using release store
   inline void synchronized_set_map(Map* value);
-  inline void synchronized_set_map_no_write_barrier(Map* value);
   inline void synchronized_set_map_word(MapWord map_word);
 
+  // Initialize the map immediately after the object is allocated.
+  // Do not use this outside Heap.
+  inline void set_map_after_allocation(
+      Map* value, WriteBarrierMode mode = UPDATE_WRITE_BARRIER);
+
   // During garbage collection, the map word of a heap object does not
   // necessarily contain a map pointer.
   inline MapWord map_word() const;