Enhancement SUP-14030
When a selection intersects with an block/editable, and a deletion (keypress, paste, cut) would occur, each block/editable emits a cancelable event.
If one of these events is canceled, the event causing the deletion is canceled.
Bugfix SUP-10337
When nesting editables into blocks, which were nested into other blocks, in some situations, pressing the “delete“ or “forwarddelete” key
would call the confirmedDestroy() method of the inner block (which would show a dialog to ask, whether the block should be deleted),
although the shouldDestroy() method of the block returned false (effectively preventing the block from being deleted).
This has been fixed now, so that confirmedDestroy() is only called, when the block actually can be deleted (shouldDestroy() returns true).