rustc_mir_build: reorder bindings
No functional changes intended.
I'm playing around with building compiler components using nightly rust
(2021-11-02) in a non-standard way. I encountered the following error while
trying to build rustc_mir_build:
```
error[E0597]: `wildcard` does not live long enough
--> rust/src/nightly/compiler/rustc_mir_build/src/build/matches/mod.rs:1767:82
|
1767 | let mut otherwise_candidate = Candidate::new(expr_place_builder.clone(), &wildcard, false);
| ^^^^^^^^^ borrowed value does not live long enough
...
1799 | }
| -
| |
| `wildcard` dropped here while still borrowed
| borrow might be used here, when `guard_candidate` is dropped and runs the destructor for type `Candidate<'_, '_>`
|
= note: values in a scope are dropped in the opposite order they are defined
```
I believe this flags an issue that may become an error in the future.
Swapping the order of `wildcard` and `guard_candidate` resolves it.