Bug 399575

SUMMARY
When undoing creation of a layer with content on it, it remains visible.

STEPS TO REPRODUCE
1. New document
2. Draw on Layer 2
3. Duplicate Layer 2
4. Hide Layer 2 (eye in docker)
5. Undo

OBSERVED RESULT
Duplicated layer is still visible even though it is removed and no other layers except Layer 1 are visible.

EXPECTED RESULT
No layers should be visible except Layer 1.

SOFTWARE VERSIONS
Qt Version: 5.11.2-1

ADDITIONAL INFORMATION
This was just one method. Layers do not have to be hidden nor does it have to be a duplicated layer.

Here's another example which shows some other issues with layers: (and how it was originally discovered)
1. New document
2. Draw something on Layer 2
3. Create new Layer 3
4. Draw on new Layer 3
5. Delete Layer 3
6. Draw something on Layer 2 (cannot do next steps unless this is done, deletion not added to undo stack)
7. Undo twice
8. Redo