List music playing on a member part of a group but not coordinator

[goldyfruit]

If a speaker is part of a group but it's not the coordinator then during the what is playing intent only the coordinator will be listed as having a music playing on it.

The not coordinator member will have the PLAYING state via the get_current_transport_info() method but the get_current_track_info() method will return empty dict values.

{'title': '', 'artist': '', 'album': '', 'album_art': '', 'position': 'NOT_IMPLEMENTED', 'playlist_position': '1', 'duration': 'NOT_IMPLEMENTED', 'uri': 'x-rincon:RINCON_5CAAFD9C48EC01400', 'metadata': 'NOT_IMPLEMENTED'}

When the coordinator is full of values.