element-permitted-content false positive in textarea

<textarea>
    <ul>
        <li>hello</li>
    </ul>
<textarea>

Shouldn't report a element-permitted-content error for "ul" (obviously - this is a bad practice, but it's valid generally and unfortunately common)

I guess text in textarea should be generally treated as separate context, similar to how it was done for template in #305 (closed)

Unlike for template, element-required-ancestor shouldn't be changed for textarea though?