Ternary operator no longer promotes characters to integers [Part 2]

[SSoulaimane]

Re-enable test from #7041.

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[PetarKirov]

@SSoulaimane @thewilsonator wasn't there consensus that the common type of any two types T and U is T if U is convertible to T and U if T is convertible to U? Or in other words, that the common type of char and wchar is wchar?

[thewilsonator]

byte b;
short s;
auto u = 0 ? b : s;
pragma(msg, typeof(u));

prints int.

[SSoulaimane]

This was made withing the current practice of preemptive promotion even for ternary expressions. If/when that's going to change, it will affect more than just char/wchar but also the rest of the basic types.

[SSoulaimane]

Here is a DMD PR for that dlang/dmd#9943.