Icons: Allow additional SVG elements and attributes in the icon sanitizer

[t-hamano]

This PR is a subset of #12197, focusing only on allowing the SVG elements and attributes needed for core icons to render correctly.

Related Gutenberg PR:

• Icons: Test the registry sanitizer with a data provider gutenberg#83024

Trac ticket: https://core.trac.wordpress.org/ticket/65795

Use of AI Tools

AI assistance: Yes
Tool(s): Claude Code
Model(s): Claude Opus 5
Used for: Porting the Gutenberg changes, writing tests, and drafting this description; reviewed by me.

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[t-hamano]

This test is updated because stroke-width is now preserved, so checking for the width= string would match it. The attributes are inspected directly instead.

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[westonruter]

Minor: All of these associative arrays can be simplified by using array_fill_keys(), which eliminates the pains of aligning the =>.

Suggested change

	$stroke_attributes = array(
	'style' => true,
	'stroke' => true,
	'stroke-width' => true,
	'stroke-linecap' => true,
	'stroke-linejoin' => true,
	'stroke-miterlimit' => true,
	'vector-effect' => true,
	);
	$stroke_attributes = array_fill_keys(
	array(
	'style',
	'stroke',
	'stroke-width',
	'stroke-linecap',
	'stroke-linejoin',
	'stroke-miterlimit',
	'vector-effect',
	),
	true
	);

I recall we did this for some other Kses tests already, or we talked about it.

Same goes for the following associative arrays as well.

A helper method could make this more concise, or even a closure in this method:

$generate_array = static function ( string ...$tag_names ): array {
	return array_fill_keys( $tag_names, true );
};

Then the above can be just:

		$stroke_attributes = $generate_array(
			'style',
			'stroke',
			'stroke-width',
			'stroke-linecap',
			'stroke-linejoin',
			'stroke-miterlimit',
			'vector-effect',
		);

[t-hamano]

Nice idea. That reminds me of our past discussion. Based on WordPress/gutenberg#75550 (comment), I have decided to use the get_allowed_attribute_list() private method.

Fixed in 706b8a8

[westonruter]

Pre-approving.

[t-hamano]

Committed: https://core.trac.wordpress.org/changeset/63652