Revert "Move discovery client to its own package"

pkg/api/unversioned/helpers.go

@@ -92,13 +92,3 @@ func FormatLabelSelector(labelSelector *LabelSelector) string {
 	}
 	return l
 }
-
-func ExtractGroupVersions(l *APIGroupList) []string {
-	var groupVersions []string
-	for _, g := range l.Groups {
-		for _, gv := range g.Versions {
-			groupVersions = append(groupVersions, gv.GroupVersion)
-		}
-	}
-	return groupVersions
-}