Propagate ObjectFlags.NonInferrableType through widening

Author: ahejlsberg

src/compiler/checker.ts

@@ -14231,7 +14231,7 @@ namespace ts {
             const result = createAnonymousType(type.symbol, members, emptyArray, emptyArray,
                 stringIndexInfo && createIndexInfo(getWidenedType(stringIndexInfo.type), stringIndexInfo.isReadonly),
                 numberIndexInfo && createIndexInfo(getWidenedType(numberIndexInfo.type), numberIndexInfo.isReadonly));
-            result.objectFlags |= (getObjectFlags(type) & ObjectFlags.JSLiteral); // Retain js literal flag through widening
+            result.objectFlags |= (getObjectFlags(type) & (ObjectFlags.JSLiteral | ObjectFlags.NonInferrableType)); // Retain js literal flag through widening
             return result;
         }