Chance the Rapper, the announced headliner of Artillery’s “Black Diaspora Emerging” forum at Glendale Public Library January 28, was sidelined by a sudden illness, disappointing the organizers and many attendees. But even if the Black Star Line failed to dock in so-white and far-up-river Glendale, a lively discussion of Black art issues ensued among three panelists, touching on subjects from Basquiat to the multi-national Lakers line-up.