Use LookupIterator for elements in GetAccessor

BUG=v8:4137
LOG=n

Review URL: https://codereview.chromium.org/1178083002

Cr-Commit-Position: refs/heads/master@{#28962}

src/objects.cc

@@ -6573,37 +6573,12 @@ MaybeHandle<Object> JSObject::GetAccessor(Handle<JSObject> object,
 
   // Make the lookup and include prototypes.
   uint32_t index = 0;
-  if (name->AsArrayIndex(&index)) {
-    for (PrototypeIterator iter(isolate, object,
-                                PrototypeIterator::START_AT_RECEIVER);
-         !iter.IsAtEnd(); iter.Advance()) {
-      Handle<Object> current = PrototypeIterator::GetCurrent(iter);
-      // Check access rights if needed.
-      if (current->IsAccessCheckNeeded() &&
-          !isolate->MayAccess(Handle<JSObject>::cast(current))) {
-        isolate->ReportFailedAccessCheck(Handle<JSObject>::cast(current));
-        RETURN_EXCEPTION_IF_SCHEDULED_EXCEPTION(isolate, Object);
-        return isolate->factory()->undefined_value();
-      }
+  LookupIterator::Configuration c =
+      LookupIterator::PROTOTYPE_CHAIN_SKIP_INTERCEPTOR;
+  LookupIterator it = name->AsArrayIndex(&index)
+                          ? LookupIterator(isolate, object, index, c)
+                          : LookupIterator(object, name, c);
 
-      if (current->IsJSObject() &&
-          Handle<JSObject>::cast(current)->HasDictionaryElements()) {
-        JSObject* js_object = JSObject::cast(*current);
-        SeededNumberDictionary* dictionary = js_object->element_dictionary();
-        int entry = dictionary->FindEntry(index);
-        if (entry != SeededNumberDictionary::kNotFound) {
-          Object* element = dictionary->ValueAt(entry);
-          if (dictionary->DetailsAt(entry).type() == ACCESSOR_CONSTANT &&
-              element->IsAccessorPair()) {
-            return handle(AccessorPair::cast(element)->GetComponent(component),
-                          isolate);
-          }
-        }
-      }
-    }
-  } else {
-    LookupIterator it(object, name,
-                      LookupIterator::PROTOTYPE_CHAIN_SKIP_INTERCEPTOR);
   for (; it.IsFound(); it.Next()) {
     switch (it.state()) {
       case LookupIterator::INTERCEPTOR:
@@ -6634,7 +6609,7 @@ MaybeHandle<Object> JSObject::GetAccessor(Handle<JSObject> object,
       }
     }
   }
-  }
+
   return isolate->factory()->undefined_value();
 }