[heap] RecordWrites iterates black object to ensure marking progress.

src/objects.cc

Index: src/objects.cc
diff --git a/src/objects.cc b/src/objects.cc
index 7e3a325a6df6c337b5a8b0fc604f8204ff09ce5e..2ae1d04e134928bc8c31880f7464c4033f445b6a 100644
--- a/src/objects.cc
+++ b/src/objects.cc
@@ -3200,7 +3200,7 @@ void Map::ReplaceDescriptors(DescriptorArray* new_descriptors,
   }
 
   DescriptorArray* to_replace = instance_descriptors();
-  GetHeap()->incremental_marking()->RecordWrites(to_replace);
+  GetHeap()->incremental_marking()->IterateBlackObject(to_replace);
   Map* current = this;
   while (current->instance_descriptors() == to_replace) {
     Object* next = current->GetBackPointer();
@@ -4574,7 +4574,7 @@ void Map::EnsureDescriptorSlack(Handle<Map> map, int slack) {
   }
 
   // Replace descriptors by new_descriptors in all maps that share it.
-  map->GetHeap()->incremental_marking()->RecordWrites(*descriptors);
+  map->GetHeap()->incremental_marking()->IterateBlackObject(*descriptors);
 
   Map* current = *map;
   while (current->instance_descriptors() == *descriptors) {