Remove custom weak handling of monomorphic IC.

src/heap/objects-visiting-inl.h

Index: src/heap/objects-visiting-inl.h
diff --git a/src/heap/objects-visiting-inl.h b/src/heap/objects-visiting-inl.h
index f0637932d6299e9a37c83e074cf8cff59c4b98f9..e6334f365bc250c56b3725ac6f1d69474b35bec6 100644
--- a/src/heap/objects-visiting-inl.h
+++ b/src/heap/objects-visiting-inl.h
@@ -263,10 +263,9 @@ void StaticMarkingVisitor<StaticVisitor>::VisitCodeTarget(Heap* heap,
   // to be serialized.
   if (FLAG_cleanup_code_caches_at_gc && target->is_inline_cache_stub() &&
       !target->is_call_stub() &&
-      ((heap->flush_monomorphic_ics() && !target->is_weak_stub()) ||
+      ((heap->flush_monomorphic_ics() && !target->embeds_maps_weakly()) ||
        heap->isolate()->serializer_enabled() ||
-       target->ic_age() != heap->global_ic_age() ||
-       target->is_invalidated_weak_stub())) {
+       target->ic_age() != heap->global_ic_age())) {
     ICUtility::Clear(heap->isolate(), rinfo->pc(),
                      rinfo->host()->constant_pool());
     target = Code::GetCodeFromTargetAddress(rinfo->target_address());
@@ -508,10 +507,7 @@ void StaticMarkingVisitor<StaticVisitor>::VisitConstantPoolArray(
     bool is_weak_object =
         (array->get_weak_object_state() ==
              ConstantPoolArray::WEAK_OBJECTS_IN_OPTIMIZED_CODE &&
-         Code::IsWeakObjectInOptimizedCode(object)) ||
-        (array->get_weak_object_state() ==
-             ConstantPoolArray::WEAK_OBJECTS_IN_IC &&
-         Code::IsWeakObjectInIC(object));
+         Code::IsWeakObjectInOptimizedCode(object));
     if (!is_weak_object) {
       StaticVisitor::MarkObject(heap, object);
     }