Revert of [heap] Reland "Make non-atomic markbit operations consistent with atomic ones."

src/heap/heap.cc

Index: src/heap/heap.cc
diff --git a/src/heap/heap.cc b/src/heap/heap.cc
index 30e55ca97466cab50a9da0a853e96cb626d43e10..0c33fcee034923068acafc538440a19de40cfa3c 100644
--- a/src/heap/heap.cc
+++ b/src/heap/heap.cc
@@ -4270,7 +4270,7 @@
 void Heap::NotifyObjectLayoutChange(HeapObject* object,
                                     const DisallowHeapAllocation&) {
   if (FLAG_incremental_marking && incremental_marking()->IsMarking()) {
-    incremental_marking()->WhiteToGreyAndPush(object);
+    incremental_marking()->MarkGrey(object);
   }
 #ifdef VERIFY_HEAP
   DCHECK(pending_layout_change_object_ == nullptr);
@@ -4834,7 +4834,7 @@
     // promoted objects.
     if (heap_->incremental_marking()->black_allocation()) {
       Code* code = Code::cast(Code::GetObjectFromEntryAddress(code_entry_slot));
-      heap_->incremental_marking()->WhiteToGreyAndPush(code);
+      heap_->incremental_marking()->MarkGrey(code);
     }
   }
 
@@ -5628,7 +5628,7 @@
   HeapObject* heap_object = HeapObject::cast(*object);
   DCHECK(Contains(heap_object));
   if (FLAG_incremental_marking_wrappers && incremental_marking()->IsMarking()) {
-    incremental_marking()->WhiteToGreyAndPush(heap_object);
+    incremental_marking()->MarkGrey(heap_object);
   } else {
     DCHECK(mark_compact_collector()->in_use());
     mark_compact_collector()->MarkObject(heap_object);