http://europa.eu/rapid/press-release_IP-16-1492_en.htm (fifth paragraph)
But for this case, they are using a definition that makes Android even more dominant: they allege that Google restricts device manufacturers' freedoms. And from a device manufacturer point of view, Android has a 90+% market share of "licensable smart mobile operating systems", with "licensable" being key: as a device manufacturer, you cannot use iOS, so that doesn't count if you buy into this line of argument: