code: func unsourceMappings(p *profile.Profile) {
  	for _, m := range p.Mapping {
  		if m.BuildID == "" {
  			if u, err := url.Parse(m.File); err == nil && u.IsAbs() {
  				m.File = ""
  			}
  		}
  	}
  }
docs: // unsourceMappings iterates over the mappings in a profile and replaces file
  // set to the remote source URL by collectMappingSources back to empty string.