Bug 393584

Issue: The reference image tool provides the same contextual menu as the vectors on a new document *if* no vector layer exist.

To reproduce:
-make new document
-select the Ref-images-tool
-place one or more ref images
-right click on them

result: menu items group/ungroup and logical-operations are shown. If any of these are used, Krita makes a new vector layer and places all images there.

expected result: only applicable menu entries should display on right click.

Notes:

-Creating a vector layer prior to using the Ref-images-tool and properly selecting that layer, prevents the appearing of the full vector menu on first run.

-Creating a vector layer after using the Ref-images-tool and selecting the layer will remove the extra vector menu items. this is will "fix" the menu, to display properly.

-Using the extra menu items on the reference images will place them in a new vector layer, now if undo this steps, the images will go back to the Ref-images-Tool properly, after this even without the self-created vector layer, the menu will start displaying properly.

-Also once the menu has been "fixed" with any of the above, will reamin correct for the rest of the session.