librustc: Use Typer's node_ty method instead of free function in ExprUseVisitor.
Add test.
auto merge of #16753 : luqmana/rust/typer-ty, r=nikomatsakis

We shouldn't be making calls directly to `ty::node_id_to_type` since the typer may be bcx which also has to monomorphize the type.

Fixes #16643.