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

common/auth/localauth/server_test.go

 // Copyright 2017 The LUCI Authors. All rights reserved.
 // Use of this source code is governed under the Apache License, Version 2.0
 // that can be found in the LICENSE file.
 
 package localauth
 
 import (
         "bytes"
         "encoding/json"
         "fmt"
         "io"
         "io/ioutil"
         "net/http"
         "strings"
         "testing"
         "time"
 
         "golang.org/x/net/context"
         "golang.org/x/oauth2"
 
         "github.com/luci/luci-go/common/clock"
         "github.com/luci/luci-go/common/clock/testclock"
         "github.com/luci/luci-go/common/errors"
+        "github.com/luci/luci-go/common/retry"
         "github.com/luci/luci-go/lucictx"
 
         . "github.com/luci/luci-go/common/testing/assertions"
         . "github.com/smartystreets/goconvey/convey"
 )
 
 func TestServerLifecycle(t *testing.T) {
         t.Parallel()
 
         ctx := context.Background()
@@ skipping 221 matching lines @@
 
                 Convey("Token generator returns ErrorWithCode", func() {
                         responses <- errWithCode{
                                 error: fmt.Errorf("with code"),
                                 code:  123,
                         }
                         So(call(goodRequest()), ShouldEqual, `HTTP 200 (json): {"error_code":123,"error_message":"with code"}`)
                 })
 
                 Convey("Token generator returns transient error", func() {
-                        responses <- errors.WrapTransient(fmt.Errorf("transient"))
+                        responses <- errors.New("transient", retry.Tag)
                         So(call(goodRequest()), ShouldEqual, `HTTP 500: Transient error - transient`)
                 })
         })
 }
 
 type errWithCode struct {
         error
         code int
 }
 
@@ skipping 38 matching lines @@
                 panic(err)
         }
 
         tp := ""
         if resp.Header.Get("Content-Type") == "application/json; charset=utf-8" {
                 tp = " (json)"
         }
 
         return fmt.Sprintf("HTTP %d%s: %s", resp.StatusCode, tp, strings.TrimSpace(string(blob)))
 }