Text jumps up after removing list

[Jakub Ś]

Based on #12323.

Open editor with following content:

<ul>
  <li>one</li>
  <li>two</li>
</ul>
<p>hello</p>

2. Select whole list.
3. Delete list by pressing backspace.
4. Click on line with "hello"

Result: text will jump up to first line.

[Piotrek Koszuliński]

There's a code in editable.js which don't handle autoparagraphing at all. I guess there's a filler char created, because that code tries to put the selection before <p> and then moving the selection somewhere else results in removing filler char hence text jump.