Drag and drop recordering breaks previous removal of nodes

If you remove nodes and then drag later nodes into the position of the removed nodes, the position is wrongly set and the nodes flagged as being removed aren't actually removed after saving changes.

See screenshots for example.

6 nodes in a queue.

1. Remove node at position 1.
2. Remove node at position 2.
3. All correct so far.
4. Drag node at original position 5 to new position 1.
5. New node at position 1 is incorrectly shown as having a position of "3".
6. Drag node at original position 6 to new position 2.
7. New node at position 2 is incorrectly shown as having a position of "4".
8. Save changes.

Result:
new position 1 = node at original position 1 (not removed)
new position 2 = node at original position 2 (not removed)
new position 3 = node at original position 5
new position 4 = node at original position 6
new position 5 = node at original position 3
new position 6 = node at original position 4