Represents drmModeConnector; both connected and disconnected. Currently
only provides non-changing meta data. MetaOutputKms is changed to use
MetaKmsConnector to get basic metadata, but variable metadata, those
changing depending on what is connected (e.g. physical dimension, EDID,
etc), are still manually retrieved by MetaOutputKms.
https://gitlab.gnome.org/GNOME/mutter/issues/548https://gitlab.gnome.org/GNOME/mutter/merge_requests/525