Bug Description

When a plugin generates a validation error by rendering invalid code in the block editor, the AMP Validation sidebar says WordPress core is the error source:

It seems the logic in the editor sidebar needs to be updated to treat Gutenberg like WordPress core, and also to ignore WordPress core when there is another source (e.g. a theme/plugin).

See: #6610 (comment)

Steps to reproduce

1. Create a new plugin that will add a shortcode. The shortcode should generate invalid AMP markup, e.g.:

<?php
/*
Plugin Name: Bad Tag Shortcode
*/

add_shortcode( 'bad-tag-shortcode', function () {
	return '<bad-tag-shortcode></bad-tag-shortcode>';
} );

2. Create a new post and add the new [bad-tag-shortcode] (via the Shortcode block).
3. Save and check out the AMP Validation sidebar in the block editor. It should say that the WordPress core is responsible for the <bad-tag-shortcode> error:
   

Expected Behaviour

The logic in the editor sidebar needs to be updated to treat Gutenberg like WordPress core, and also to ignore WordPress core when there is another source (e.g. a theme/plugin).

Screenshots

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PHP Version

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Plugin Version

2.2.0-alpha

AMP plugin template mode

Transitional

WordPress Version

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Site Health

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Gutenberg Version

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OS(s) Affected

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Browser(s) Affected

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Device(s) Affected

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Acceptance Criteria

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Implementation Brief

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QA Testing Instructions

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Demo

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Changelog Entry

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