HTML API: Support INPUT tags.

Adds support for the following HTML elements to the HTML Processor:

 - INPUT

Previously this element was not supported and the HTML Processor would bail when encountering one. Now, with this patch applied, it will proceed to parse the HTML document.

Developed in https://github.com/WordPress/wordpress-develop/pull/5907
Discussed in https://core.trac.wordpress.org/ticket/60283

Props jonsurrell
See #60283



git-svn-id: https://develop.svn.wordpress.org/trunk@57343 602fd350-edb4-49c9-b593-d223f7449a82

tests/phpunit/tests/html-api/wpHtmlProcessor.php

@@ -253,7 +253,6 @@ class Tests_HtmlApi_WpHtmlProcessor extends WP_UnitTestCase {
 			'HEAD'      => array( 'HEAD' ),
 			'HTML'      => array( 'HTML' ),
 			'IFRAME'    => array( 'IFRAME' ),
-			'INPUT'     => array( 'INPUT' ),
 			'LINK'      => array( 'LINK' ),
 			'MARQUEE'   => array( 'MARQUEE' ),
 			'MATH'      => array( 'MATH' ),

tests/phpunit/tests/html-api/wpHtmlProcessorBreadcrumbs.php

@@ -180,7 +180,6 @@ class Tests_HtmlApi_WpHtmlProcessorBreadcrumbs extends WP_UnitTestCase {
 			'HEAD',
 			'HTML',
 			'IFRAME',
-			'INPUT',
 			'LINK',
 			'MARQUEE', // Deprecated.
 			'MATH',