When deleting the last ordered list item in a table cell, which entire content is a contenteditable area, we must delete the whole ordered list:

Before:
| <table>
|   border="1"
|   <tbody>
|     <tr>
|       <td>
|         <div>
|           contenteditable="true"
|           <ol>
|             <li>
|               id="li"
|               <#selection-caret>
|               <br>

After:
| <table>
|   border="1"
|   <tbody>
|     <tr>
|       <td>
|         <div>
|           contenteditable="true"
|           <div>
|             <#selection-caret>
|             <br>