Merge #7218

7218: Fix typos r=Veykril a=regexident

Apart from the very last commit on this PR (which fixes a public type's name) all changes are non-breaking.

Co-authored-by: Vincent Esche <regexident@gmail.com>

crates/parser/src/grammar/items/use_item.rs

@@ -46,7 +46,7 @@ fn use_tree(p: &mut Parser, top_level: bool) {
         // test use_tree_list
         // use {crate::path::from::root, or::path::from::crate_name}; // Rust 2018 (with a crate named `or`)
         // use {path::from::root}; // Rust 2015
-        // use ::{some::arbritrary::path}; // Rust 2015
+        // use ::{some::arbitrary::path}; // Rust 2015
         // use ::{{{root::export}}}; // Nonsensical but perfectly legal nesting
         T!['{'] => {
             use_tree_list(p);