Last layout in slot cannot be deleted, but it can be moved.

[shylux]

There is a safeguard, so that the last layout in a slot cannot be deleted.
The last layout can however be moved to another slot. Resulting in the exact case this feature tried to avoid: a slot without a layout.

I can't say what would be the best solution. Maybe recreate the default layout whenever a slot is empty?

Update: Just realized that the last layout can be deleted. This shouldn't happen, right? Maybe its because it's the portlet slot?