Reorders imports of modules containing `#![macro_use]`

[nagisa]

Similar to #2399, rustfmt will still reorder mod statements of modules that contain a #![macro_use] attribute, as opposed to the mod itself being annotated with #[macro_use]. This is equivalently invalid reordering.

rustfmt 1.4.36-nightly

[calebcartwright]

Our hands are somewhat tied as rustfmt works exclusively pre-expansion and the inner attributes on the mods aren't actually included in the attribute list on the corresponding items.

We do still peek inside the out-of-line mods during our up front mod-to-file resolution process so I wonder if we could somehow extend that existing mapping to be able to capture and tie back any inner attributes to the corresponding item.