Merge pull request #2857 from HansMuller/two_level_list_fixo

Fixed a typo

packages/flutter/lib/src/widgets/basic.dart

@@ -2593,7 +2593,7 @@ class KeyedSubtree extends StatelessWidget {
     }
 
     assert(!debugItemsHaveDuplicateKeys(itemsWithUniqueKeys));
-    return items;
+    return itemsWithUniqueKeys;
   }