Clean up some suspicious code. There's no guarantee a constant of integer type is a ConstantInt, so it's not safe to just cast<> these to ConstantInt. (It could be a constant expression, for example) The code is shorter this way too :).

module mini.delegate2;

void main()
{
    int foo = 42;
    int bar()
    {
        return foo;
    }
    int delegate() dg = &bar;
    assert(dg() == foo);
}