12c5f786ea
Fix handling of item names for HIR - Handle variants, fields, macros in `Node::ident()` - Handle the crate root in `opt_item_name` - Rewrite `item_name` in terms of `opt_item_name` I need this for both https://github.com/rust-lang/rust/pull/77820 and https://github.com/rust-lang/rust/pull/78082, so splitting it out into a separate PR so it can land early.
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