Block Hooks API: Move ignoredHookedBlocks metadata injection logic

[tjcafferkey]

Trac ticket: https://core.trac.wordpress.org/ticket/60759

Testing instructions:

1. Add the below code to your site.
2. Load the navigation block and check it renders in the editor/frontend
3. In the editor, update the navigation by adding another page and saving
4. Check the wp_postmeta table to see if core/loginout has been added to a row with the meta_key => _wp_ignored_hooked_blocks

function register_logout_block_as_navigation_last_child( $hooked_blocks, $position, $anchor_block, $context ) {
	if ( $anchor_block === 'core/navigation' && $position === 'last_child' ) {
		$hooked_blocks[] = 'core/loginout';
	}

	return $hooked_blocks;
}

add_filter( 'hooked_block_types', 'register_logout_block_as_navigation_last_child', 10, 4 );

---

This Pull Request is for code review only. Please keep all other discussion in the Trac ticket. Do not merge this Pull Request. See GitHub Pull Requests for Code Review in the Core Handbook for more details.

[tjcafferkey]

cc @ockham

[github-actions]

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[ockham]

This is shaping up nicely! 😄

[ockham]

We have some test coverage in https://github.com/WordPress/gutenberg/blob/6108134aae75d1bd4826256490c609cb29044cd8/phpunit/blocks/block-navigation-block-hooks-test.php that we can probably copy over (with some small tweaks).

[github-actions]

The following accounts have interacted with this PR and/or linked issues. I will continue to update these lists as activity occurs. You can also manually ask me to refresh this list by adding the props-bot label.

Core Committers: Use this line as a base for the props when committing in SVN:

Props bernhard-reiter, tomjcafferkey.

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[ockham]

Thank you very much, this is looking great! 🚀 Especially appreciate the test coverage, good thinking to add test cases for missing post ID and type 👍

Apologies for the number of notes I left, most of it is minor and/or coding standards compliance stuff 😬

[tjcafferkey]

@ockham I've addressed all your comments aside from the one we're going to address in a separate PR. I've also had to fix some merge conflicts with #6358

[ockham]

@ockham I've addressed all your comments aside from the one we're going to address in a separate PR. I've also had to fix some merge conflicts with #6358

Awesome, thank you very much!

We'll need to land the GB counterpart PR first; I've approved it, you wanna do the honors?

After that, we'll still need to wait for the code to be sync'd over to Core, so that the built Navigation block code in Core is updated and the "old" filter isn't still being added there if the new one is present. As always, the package sync will happen before Feature Freeze (i.e. next Tue, June 4), but probably only after the GB RC is released (this Friday). This means we'll likely land this PR on Monday 🙂

[ockham]

We'll need to land the GB counterpart PR first; I've approved it, you wanna do the honors?

I remembered you won't be able to do so today, so I want ahead and merged it 😬 Hope that's okay!

[ockham]

Committed to Core in https://core.trac.wordpress.org/changeset/58291.