This tests inserting an ordered list inside a shadow tree. WebKit should not hang.

Before:
| <div>
|   contenteditable=""
|   id="editor"
|   "\n    one"
|   <br>
|   "\n    two"
|   <br>
|   "\n"

After:
| <div>
|   contenteditable=""
|   id="editor"
|   <ol>
|     <li>
|       "one"
|       <br>
|     <li>
|       "two"
|       <br>
|   "\n"