Cancelling an edit on an already edited reply re-places old body.

[WilcoM]

The original content of your post will be placed back after an edit, if you try to edit it again and cancel that edit.

Steps to reproduce:

1. Post a reply (Body: Test!)
2. Edit that reply. (Body: Editted test!)
3. Save the edit.
4. Edit the reply again. (Body: Editted test 2!)
5. Cancel this edit.
6. Body: Test!