[clang-tools-extra] [clang-doc] Add button a toggle for light/dark theme (PR #181587)

[Erick Velez via cfe-commits]

evelez7 wrote:

> do you have an example of the output we can examine?

Yeah, here is a preview.

https://erickvelez.com/clang-doc-mustache-output/dark-light-toggle/

Like I said, I'm trying to prevent the screen flashing when the dark theme is used. Seems like a problem when using Javascript to set the theme.

> Seems like some output has changed in a way that no longer matches the CHECK lines. Probably needs a minor refactor in the project test.

Yeah, I haven't updated this branch upstream yet since I'm constantly changing the implementation right now.

https://github.com/llvm/llvm-project/pull/181587