Object::Lookup(), JSObject::*Lookup*() and JSReceiver::*Lookup*() handlified.

src/heap-snapshot-generator.cc

Index: src/heap-snapshot-generator.cc
diff --git a/src/heap-snapshot-generator.cc b/src/heap-snapshot-generator.cc
index 8c8f4ea3f55b10123642182d88a4608d75e81684..460e8aed28f90247e82e50584d58a4595b7fe313 100644
--- a/src/heap-snapshot-generator.cc
+++ b/src/heap-snapshot-generator.cc
@@ -1740,8 +1740,10 @@ String* V8HeapExplorer::GetConstructorName(JSObject* object) {
     // return its name. This is for instances of binding objects, which
     // have prototype constructor type "Object".
     Object* constructor_prop = NULL;
-    LookupResult result(heap->isolate());
-    object->LocalLookupRealNamedProperty(heap->constructor_string(), &result);
+    Isolate* isolate = heap->isolate();
+    LookupResult result(isolate);
+    object->LocalLookupRealNamedProperty(
+        isolate->factory()->constructor_string(), &result);
     if (!result.IsFound()) return object->constructor_name();
 
     constructor_prop = result.GetLazyValue();