Stop image overlays with null/blank icon state from inheriting icons

[out-of-phaze]

As far as I know, a blank image new /image added as an overlay shouldn't inherit the parent's icon. It should only do that if you add a raw icon state as an overlay, like "foo".

[wixoaGit]

I tried usr.overlays |= new /image(null, "arrow") in BYOND, and it did create an overlay with the arrow state and usr's icon. A null or empty icon_state did not use the default, however.

[github-actions]

This pull request has conflicts, please resolve those before we can evaluate the pull request.

[out-of-phaze]

I tried usr.overlays |= new /image(null, "arrow") in BYOND, and it did create an overlay with the arrow state and usr's icon. A null or empty icon_state did not use the default, however.

Huh, I held off on touching this PR because I assumed mirroring this functionality would require changes, but... I think that's what it does in this PR as is. Good to know.

[wixoaGit]

I tried usr.overlays |= new /image(null, "arrow") in BYOND, and it did create an overlay with the arrow state and usr's icon. A null or empty icon_state did not use the default, however.

Huh, I held off on touching this PR because I assumed mirroring this functionality would require changes, but... I think that's what it does in this PR as is. Good to know.

That is not what this PR does. Using a line like what I gave does not add a visible overlay.