Incorrect work of EXIST() with alias

First query returns default value, second query returns actual value.

-- Server version: 2.8.0 3f7e35d@181224 dev        

SELECT id, EXIST('bucket', 123456)  AS `bucket` FROM `vk_index_inc_node1` LIMIT 10;        
SELECT id, EXIST('bucket', 123456)  AS `bucket2` FROM `vk_index_inc_node1` LIMIT 10;

┆Issue is synchronized with this Gitlab issue

nck-2 / test-rep

Incorrect work of EXIST() with alias #1369