What happens if `self.icon_key` is not a key in `current_theme_icons`?

[kpsherva]

What happens if self.icon_key is not a key in current_theme_icons?

Should this yield an error to warn the developer or should it render the menu entry without its icon?

Originally posted by @alejandromumo in inveniosoftware/invenio-administration#23 (comment)