No completion after vec!

[lnicola]

vec![1, 2, 3]. and vec!(1, 2, 3). don't return any completions, while (vec![1, 2, 3]). works.

[Veykril]

Looks like we don't record the macro call expression itself at all when lowering to HIR, given our HIR doesn't have a macro call expression.

[Veykril]

Repro:

macro_rules! __rust_force_expr {
    ($e:expr) => {
        $e
    };
}
macro_rules! foo {
    ($elem:expr) => {
        __rust_force_expr!($elem)
    };
}
foo![0].$0