function transformHTML( html ) {
	if (
		!startsWith( html, COMMENT_START ) ||
		!endsWith( html, COMMENT_END )
	) {
		return null;
	}
	html = html.slice( COMMENT_START.length, html.length-COMMENT_END.length );
	html = trim( html );
	if ( !startsWith( html, ESLINT_PREFIX ) ) {
		return null;
	}
	return '/* ' + html + ' */';
}
Converts an HTML comment containing ESLint configuration to a JavaScript comment.

@private
@param {string} html - text content of an HTML AST node
@returns {(string|null)} null or a JavaScript comment