'Returns the image associated to `web_icon`.
`web_icon` can either be:
- an image icon [module, path]
- a built icon [icon_class, icon_color, background_color]
and it only has to call `read_image` if it\'s an image.'

@api.depends('web_icon')
def _compute_web_icon(self):

    for menu in self:
        if (menu.web_icon and (len(menu.web_icon.split(',')) == 2)):
            menu.web_icon_data = self.read_image(menu.web_icon)
