[IE8] Delete creates unordered list from ordered list

[Jakub Ś]

1. In IE8 open editor with below code

   <p>test</p>
   <ol>
   	<li>test</li>
   	<li>test</li>
   </ol>
   

2. Make the following selection (you get best result with shift+right arrow)

   <p>te^st</p>
   <ol>
   	<li>te^st</li>
   	<li>test</li>
   </ol>
   

3. Press delete key

Result: Ordered list gets changed into unordered one.

Problem can somewhat be reproduced from CKE 3.0 (orphan li elements were left) but this particular TC where one list is changed into another can be reproduced from CKEditor 3.4.2 in both CKE 3.x and 4.x.