Add "MkKeyContext" KeyContext generation function.

service/datastore/checkfilter_test.go

 // Copyright 2015 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.
 
 // adapted from github.com/golang/appengine/datastore
 
 package datastore
 
 import (
         "testing"
@@ skipping 46 matching lines @@
                                 }), ShouldBeNil)
                         }, ShouldPanic)
                         So(hit, ShouldBeFalse)
                 })
 
                 Convey("GetMulti", func() {
                         So(rds.GetMulti(nil, nil, nil), ShouldBeNil)
                         So(rds.GetMulti([]*Key{mkKey("", "", "", "")}, nil, nil).Error(), ShouldContainSubstring, "is nil")
 
                         // this is in the wrong aid/ns
-                        keys := []*Key{KeyContext{"wut", "wrong"}.MakeKey("Kind", 1)}
+                        keys := []*Key{MkKeyContext("wut", "wrong").MakeKey("Kind", 1)}
                         So(rds.GetMulti(keys, nil, func(pm PropertyMap, err error) error {
                                 So(pm, ShouldBeNil)
                                 So(err, ShouldEqual, ErrInvalidKey)
                                 return nil
                         }), ShouldBeNil)
 
                         keys[0] = mkKey("Kind", 1)
                         hit := false
                         So(func() {
                                 So(rds.GetMulti(keys, nil, func(pm PropertyMap, err error) error {
@@ skipping 52 matching lines @@
                                 So(rds.DeleteMulti([]*Key{mkKey("s~aid", "ns", "Kind", 1)}, func(error) error {
                                         hit = true
                                         return nil
                                 }), ShouldBeNil)
                         }, ShouldPanic)
                         So(hit, ShouldBeFalse)
                 })
 
         })
 }