Serializer: clear next link in weak cells.

src/objects-inl.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 //
 // Review notes:
 //
 // - The use of macros in these inline functions may seem superfluous
 // but it is absolutely needed to make sure gcc generates optimal
 // code. gcc is not happy when attempting to inline too deep.
 //
@@ skipping 1907 matching lines @@
 
 
 void WeakCell::set_next(Object* val, WriteBarrierMode mode) {
   WRITE_FIELD(this, kNextOffset, val);
   if (mode == UPDATE_WRITE_BARRIER) {
     WRITE_BARRIER(GetHeap(), this, kNextOffset, val);
   }
 }
 
 
+void WeakCell::clear_next(Heap* heap) {
+  set_next(heap->the_hole_value(), SKIP_WRITE_BARRIER);
+}
+
+
+bool WeakCell::next_cleared() { return next()->IsTheHole(); }
+
+
 int JSObject::GetHeaderSize() {
   InstanceType type = map()->instance_type();
   // Check for the most common kind of JavaScript object before
   // falling into the generic switch. This speeds up the internal
   // field operations considerably on average.
   if (type == JS_OBJECT_TYPE) return JSObject::kHeaderSize;
   switch (type) {
     case JS_GENERATOR_OBJECT_TYPE:
       return JSGeneratorObject::kSize;
     case JS_MODULE_TYPE:
@@ skipping 5348 matching lines @@
 #undef READ_SHORT_FIELD
 #undef WRITE_SHORT_FIELD
 #undef READ_BYTE_FIELD
 #undef WRITE_BYTE_FIELD
 #undef NOBARRIER_READ_BYTE_FIELD
 #undef NOBARRIER_WRITE_BYTE_FIELD
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_INL_H_