`DOMDocument::loadHTML` will parse HTML documents as ISO-8859-1 if there is no `meta[charset]` tag. This means that UTF-8-encoded HTML fragments such as those coming from JSON-LD `articleBody` field would be parsed with incorrect encoding.
In f14428e4c0, we tried to resolve it by putting `meta[charset]` tag at the start of the HTML fragment. Unfortunately, it turns out that causes parser to auto-insert a `html` element, losing the attributes of the original `html` tag.
Let’s try to insert the `meta[charset]` tag into the proper place in the HTML document.
We do not need to use the same trick with `JSLikeHTMLElement::__set`.
That expects smaller HTML fragments, not `html` documents, so creating `html` and `head` elements will not be a problem.
(cherry picked from commit efbbc86df9)
Had to strip type hints since we still target PHP 5.6.
Jan Tojnar
f1c6297e3c