Introduce IsUndefined(Isolate*) and IsTheHole(Isolate*)

src/heap/objects-visiting.cc

Index: src/heap/objects-visiting.cc
diff --git a/src/heap/objects-visiting.cc b/src/heap/objects-visiting.cc
index dfde5745ea00d58d902a4a6ecd17e3888da9a63f..19b204dbf7ddb2af2e8a6c81e5336f6e128a7713 100644
--- a/src/heap/objects-visiting.cc
+++ b/src/heap/objects-visiting.cc
@@ -212,7 +212,7 @@ Object* VisitWeakList(Heap* heap, Object* list, WeakObjectRetainer* retainer) {
         }
       }
       // Retained object is new tail.
-      DCHECK(!retained->IsUndefined());
+      DCHECK(!retained->IsUndefined(heap->isolate()));
       candidate = reinterpret_cast<T*>(retained);
       tail = candidate;