Properly resolve function type from function name

[dcodeIO]

Fixes

function FF(x: i32): i32 { return x; }
function GG(x: i32): i32 { return x + 2; }

var b = false;
assert(
  (b ? FF : GG)(1).toString()
  ==
  "3"
);

not compiling, even though

const FF = (x: i32): i32 => x;
const GG = (x: i32): i32 => x + 2;

...

compiles.