Warnings When a Style exists on database but not on FTP

On ACP - Costumize, if we've on database a style and we delete from ftp the style, like an idiot, instead of properly deleting from ACP first, then it appears some warnings on ACP, on style page, because it appears a style on the list that the folder doesnt exist on server.
This warning could be solved in any case, or showing a proper message to the admin.

It's silly I know, and very rare to occur but still.