Parentheses missing when combining multiple where statements

[henkmollema]

.Where(x => x == 1 || x == 2)
.AndWhere(x => x == 3 || x == 4)

generates

where x = 1 or x = 2 and (x = 3 or x = 4)

instead of

where (x = 1 or x = 2) and (x = 3 or x = 4)

This bug is introduced in #298