SQLite discards type and collation of IN operator when it comes with
only one operand. This leads to different results of straight comparison
using '=' operator and IN:

SELECT x FROM t1 WHERE x IN (1.0);
-- Result is empty set
SELECT x FROM t1 WHERE x = 1.0;
- - ['1']

Lets remove this strange ignorance and always take into consideration
types and collations of operands.

Closes #3934