Milo: Use custom config caching layer

luci_config/server/cfgclient/config_test.go

 // Copyright 2016 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 cfgclient
 
 import (
         "fmt"
         "net/url"
         "testing"
 
+        "github.com/luci/luci-go/common/config"
         "github.com/luci/luci-go/common/errors"
         "github.com/luci/luci-go/luci_config/server/cfgclient/backend"
 
         "golang.org/x/net/context"
 
         . "github.com/smartystreets/goconvey/convey"
 )
 
 // testingBackend is a Backend implementation that ignores Authority.
 type testingBackend struct {
@@ skipping 25 matching lines @@
                 return nil, tb.err
         }
         return tb.cloneItems(), nil
 }
 
 func (tb *testingBackend) ConfigSetURL(c context.Context, configSet string, p backend.Params) (url.URL, error) {
         tb.lastParams = p
         return tb.url, tb.err
 }
 
+func (tb *testingBackend) GetConfigInterface(c context.Context, a backend.Authority) config.Interface {
+        panic("not supported")
+}
+
 func (tb *testingBackend) cloneItems() []*backend.Item {
         clones := make([]*backend.Item, len(tb.items))
         for i, it := range tb.items {
                 clone := *it
                 clones[i] = &clone
         }
         return clones
 }
 
 type errorMultiResolver struct {
@@ skipping 152 matching lines @@
                                 panic(err)
                         }
 
                         tb.url = *u
                         uv, err := GetConfigSetURL(c, AsService, "")
                         So(err, ShouldBeNil)
                         So(uv, ShouldResemble, url.URL{Scheme: "https", Host: "example.com", Path: "/foo/bar"})
                 })
         })
 }