Patch description:
- Reports "Nothing selected" only when all objects has no selection
and it is in Separate type(Mode)
- Tested all types (Seperate/By Material/By loose parts)
- Instead of using
```
BKE_view_layer_array_from_objects_in_edit_mode_unique_data
```
I used
```
BKE_view_layer_array_from_bases_in_edit_mode_unique_data
```
Because it needs the "Base" not the "Object" itself.
Maniphest Tasks: T54643
Differential Revision: https://developer.blender.org/D3267
5e915baec4