Elements: Deprecate old block support filter callbacks

[aaronrobertshaw]

Addresses: #59535 (comment)

What?

• Deprecates remove block support filter callback function
• Deprecates argument for callback function that was moved to a different filter
• Fixes some code style issues

Why?

Whether the callback functions were part of a private API and not documented publicly or not, if it could be used, it might have been so better to deprecate the function or argument as required.

How?

• Deprecates gutenberg_render_elements_support
• Deprecates string value for first argument for gutenberg_render_elements_support_styles (now it is used with render_block_data the arg should be an array).
• Fixes some code style issues

Testing Instructions

1. Run unit tests: npm run test:unit:php:base -- --filter WP_Block_Supports_Elements_Test
2. Test element styles can still be applied and rendered correctly on the frontend following the steps over on Elements: Merge element style and classname generation to single filter #59535.

Next Steps

• Iterate on this alongside the corresponding backport of Elements: Merge element style and classname generation to single filter #59535

[github-actions]

This pull request changed or added PHP files in previous commits, but none have been detected in the latest commit.

Thank you! ❤️

[aaronrobertshaw]

I'll be AFK for just over a week, so my connection and bandwidth might be limited in addressing any feedback until the middle of next week.

[github-actions]

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Co-authored-by: aaronrobertshaw <aaronrobertshaw@git.wordpress.org>
Co-authored-by: andrewserong <andrewserong@git.wordpress.org>
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[andrewserong]

Thanks for the follow-up! The elements styles are still being output correctly, and the deprecated calls all look good to me. I'm not super confident with my understanding of PHP deprecated calls, though, so it might be worth getting a second opinion from @peterwilsoncc, but overall this LGTM!

[peterwilsoncc]

Acknowledging I've seen this but I'm ignoring anything that isn't going to hit WordPress 6.5 until after the release.

[peterwilsoncc]

This looks good to me folks, just a minor note about a self referential deprecation notice.

Once that's fixed, this is good to merge.

[peterwilsoncc]

This refers to itself as the replacement in the third param.

[aaronrobertshaw]

Thanks for catching that @peterwilsoncc! 🙈

I've fixed it and the docblock in 92ebee5

[aaronrobertshaw]

The changes from this PR and #59535 are combined in a single backport available in WordPress/wordpress-develop#6214.