This test drags a selection of a couple of <li> and drops them after another <li> in the same list. It verifies that no empty <li> (actually with a <br> inside) are left after the moving operation.

The original list looks like this. 'two' and 'three' are selected and are going to be dropped after 'four':
| "
"
| <li>
|   id="one"
|   "one"
| <li>
|   id="two"
|   "<#selection-anchor>two"
| <li>
|   id="three"
|   "three<#selection-focus>"
| <li>
|   id="four"
|   "four"
| "
"

'two' and 'three' should appear as <li> after 'four' and no empty <li> (nor a <br> placeholder) should be there:
| "
"
| <li>
|   id="one"
|   "one"
| <li>
|   id="four"
|   "four"
| <li>
|   id="two"
|   "two"
| <li>
|   id="three"
|   "three"
| "
"
