…llaumeGomez

Rollup of 7 pull requests

Successful merges:

 - rust-lang#114032 (typos)
 - rust-lang#114059 (rustdoc: fix cross-crate `impl Sized` & `impl ?Sized`)
 - rust-lang#114088 (Bump syn dependency)
 - rust-lang#114091 (docs: fmt::Debug*: Fix comments for finish method.)
 - rust-lang#114109 (Docs: Fix URL for `rmatches`)
 - rust-lang#114117 (Restore region uniquification in the new solver 🎉  )
 - rust-lang#114123 (Turns out opaque types can have hidden types registered during mir validation)

r? `@ghost`
`@rustbot` modify labels: rollup

Lots of tiny incremental simplifications of `EmitterWriter` internals

ignore the first commit, it's rust-lang#114088 squashed and rebased, but it's needed to use to use `derive_setters`, as they need a newer `syn` version.

Then this PR starts out with removing many arguments that are almost always defaulted to `None` or `false` and replace them with builder methods that can set these fields in the few cases that want to set them.

After that it's one commit after the other that removes or merges things until everything becomes some very simple trait objects

Lots of tiny incremental simplifications of `EmitterWriter` internals

ignore the first commit, it's rust-lang/rust#114088 squashed and rebased, but it's needed to use to use `derive_setters`, as they need a newer `syn` version.

Then this PR starts out with removing many arguments that are almost always defaulted to `None` or `false` and replace them with builder methods that can set these fields in the few cases that want to set them.

After that it's one commit after the other that removes or merges things until everything becomes some very simple trait objects

Lots of tiny incremental simplifications of `EmitterWriter` internals

ignore the first commit, it's rust-lang/rust#114088 squashed and rebased, but it's needed to use to use `derive_setters`, as they need a newer `syn` version.

Then this PR starts out with removing many arguments that are almost always defaulted to `None` or `false` and replace them with builder methods that can set these fields in the few cases that want to set them.

After that it's one commit after the other that removes or merges things until everything becomes some very simple trait objects

Lots of tiny incremental simplifications of `EmitterWriter` internals

ignore the first commit, it's rust-lang/rust#114088 squashed and rebased, but it's needed to use to use `derive_setters`, as they need a newer `syn` version.

Then this PR starts out with removing many arguments that are almost always defaulted to `None` or `false` and replace them with builder methods that can set these fields in the few cases that want to set them.

After that it's one commit after the other that removes or merges things until everything becomes some very simple trait objects

Lots of tiny incremental simplifications of `EmitterWriter` internals

ignore the first commit, it's rust-lang/rust#114088 squashed and rebased, but it's needed to use to use `derive_setters`, as they need a newer `syn` version.

Then this PR starts out with removing many arguments that are almost always defaulted to `None` or `false` and replace them with builder methods that can set these fields in the few cases that want to set them.

After that it's one commit after the other that removes or merges things until everything becomes some very simple trait objects

Lots of tiny incremental simplifications of `EmitterWriter` internals

ignore the first commit, it's rust-lang/rust#114088 squashed and rebased, but it's needed to use to use `derive_setters`, as they need a newer `syn` version.

Then this PR starts out with removing many arguments that are almost always defaulted to `None` or `false` and replace them with builder methods that can set these fields in the few cases that want to set them.

After that it's one commit after the other that removes or merges things until everything becomes some very simple trait objects