Theme: Option to prefer system UI theme in theme selector

[ishank-s]

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[jyn514]

Don't we already support this?

[Nemo157]

Yes, this has been implementing in rustdoc for a few years now, only if you open really old docs will it be missing. Docs.rs itself doesn't have a theme selector, but will follow whatever the last loaded docs do. This does mean that navigating to a non-rustdoc page like https://docs.rs won't auto-update if your system preference has changed, but as long as you have any rustdoc page open (and JS enabled) we propagate the theme selection throughout all docs.rs pages instantly.

[jyn514]

Ok, I'm going to close this as a duplicate of #464 then