List gets styled when pressing delete

[Jakub Ś]

Please refer to: 12284.

1. Paste below code into editor and switch to source:

   <p>text&nbsp;<strong>bold</strong></p>
   <ol>
   	<li>item</li>
   </ol>
   

2. Put cursor at the end of bold (make sure you are inside bold by looking at element's path)
3. Press delete

Result: List item gets bold.

---

If there is paragraph instead of list below the bold paragraph, it won't get bolded/styled on delete.

<p>text&nbsp;<strong>bold</strong></p>
<p>text</p>

Problem can be reproduced from CKEditor 3.6.5 rev. [7620]