Add Kind/StringID/IntID back to Key.

service/datastore/multiarg.go

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 package datastore
 
 import (
         "fmt"
         "reflect"
 
@@ skipping 257 matching lines @@
 
         // get parent
         par, _ := pls.GetMetaDefault("parent", nil).(*Key)
 
         return NewKey(aid, ns, kind, sid, iid, par), nil
 }
 
 func setKey(src interface{}, key *Key) {
         pls := mkPLS(src)
         if pls.SetMeta("key", key) == ErrMetaFieldUnset {
-                lst := key.Last()
+                lst := key.LastTok()
                 if lst.StringID != "" {
                         _ = pls.SetMeta("id", lst.StringID)
                 } else {
                         _ = pls.SetMeta("id", lst.IntID)
                 }
                 _ = pls.SetMeta("kind", lst.Kind)
                 _ = pls.SetMeta("parent", key.Parent())
         }
 }
 
 func mkPLS(o interface{}) PropertyLoadSaver {
         if pls, ok := o.(PropertyLoadSaver); ok {
                 return pls
         }
         return GetPLS(o)
 }