[errors] de-specialize Transient in favor of Tags.

common/gcloud/gs/gs.go

Index: common/gcloud/gs/gs.go
diff --git a/common/gcloud/gs/gs.go b/common/gcloud/gs/gs.go
index 4ed0dde7b9784976b9aa1fce4dcff98b647df20d..6f6b867ad906f1d985cd3420562776e5f3cb2bb1 100644
--- a/common/gcloud/gs/gs.go
+++ b/common/gcloud/gs/gs.go
@@ -141,7 +141,7 @@ func (c *prodClient) Rename(src, dst Path) error {
 			}
 
 			// Assume all unexpected errors are transient.
-			return errors.WrapTransient(err)
+			return retry.Tag.Apply(err)
 		}
 		return nil
 	}, func(err error, d time.Duration) {
@@ -186,7 +186,7 @@ func (c *prodClient) deleteObject(o *gs.ObjectHandle) error {
 			}
 
 			// Assume all unexpected errors are transient.
-			return errors.WrapTransient(err)
+			return retry.Tag.Apply(err)
 		}
 		return nil
 	}, func(err error, d time.Duration) {