Co-authored-by: Miguel Ojeda <ojeda@users.noreply.github.com>

Co-authored-by: bluss <bluss@users.noreply.github.com>

Co-authored-by: bluss <bluss@users.noreply.github.com>

Co-authored-by: Tyler Mandry <tmandry@gmail.com>

They are never both `None` or both `Some`, so it makes more sense to use
an enum so that we "make impossible states impossible".

…stdoc

…dePro, r=GuillaumeGomez

Update Source Code Pro and include italics

Fixes rust-lang#65502.

rust-lang#65665, a similar PR to this was merged but reverted because of rust-lang#65665 (comment).

The issue in that comment is the upstream issue adobe-fonts/source-code-pro#217 which should now be fixed in the upstream since [2.032R-ro/1.052R-it/1.012R-VAR release](https://github.com/adobe-fonts/source-code-pro/releases/tag/2.032R-ro/1.052R-it/1.012R-VAR), so I think this can now be merged.

A couple of notes from the original PR:
* Since this PR changes the font set, I think docs.rs would have to be updated if this PR is merged.
* The fonts have a double extension (.ttf.woff); this is to keep the names consistent with the upstream font release which does that to distinguish these from the .otf.woff files (Source Code Pro otf renders poorly on older Windows system apps).

…imulacrum

Update RELEASES.md for 1.51.0

### [Rendered](https://github.com/rust-lang/rust/blob/relnotes-1.51.0/RELEASES.md)

r? `@Mark-Simulacrum`
cc `@rust-lang/release`

…=Nemo157

Remove theme.js file

Fixes rust-lang#82616.

The first commit moves the `theme.js` file into `main.js`, which requires to also run a small `.replace` on the `main.js` content.

The second commit is just a small cleanup to centralize DOM ids.

Since it removes a file from rustdoc output: cc `@rust-lang/docs-rs`

cc `@jsha`
r? `@jyn514`

…uillaumeGomez

rustdoc: Replace pair of `Option`s with an enum

They are never both `None` or both `Some`, so it makes more sense to use
an enum so that we "make impossible states impossible".

…lett

rename :pat2018 -> :pat2015

as requested by T-lang on zulip: https://rust-lang.zulipchat.com/#narrow/stream/213817-t-lang/topic/or.20patterns/near/231133873

No functional changes here... just renaming.

r? `@nikomatsakis`

…=jonas-schievink

⬆️ rust-analyzer

add rust-analyzer rustc_private option in librustdoc Cargo.toml

This addition will allow to have code completion while hacking rustdoc with rust-analyzer.

more info: https://rust-analyzer.github.io/manual.html#rust-analyzer.rustcSource

r? `@jyn514`