Revert of Migrate tsmon protos to proto3

appengine/tsmon/standardmetrics_test.go

 // Copyright 2016 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 tsmon
 
 import (
         "testing"
 
+        "github.com/golang/protobuf/proto"
         "github.com/luci/luci-go/common/tsmon"
         "github.com/luci/luci-go/common/tsmon/monitor"
         "github.com/luci/luci-go/common/tsmon/store"
         "github.com/luci/luci-go/common/tsmon/target"
 
         . "github.com/smartystreets/goconvey/convey"
 )
 
 func TestStandardMetrics(t *testing.T) {
         Convey("Default version", t, func() {
                 c, _ := buildGAETestContext()
-                tsmon.GetState(c).S = store.NewInMemory(&target.Task{ServiceName: "default target"})
+                tsmon.GetState(c).S = store.NewInMemory(&target.Task{ServiceName: proto.String("default target")})
                 standardMetricsCallback(c)
                 tsmon.Flush(c)
 
                 monitor := tsmon.GetState(c).M.(*monitor.Fake)
                 So(len(monitor.Cells), ShouldEqual, 1)
                 So(monitor.Cells[0][0].Name, ShouldEqual, "appengine/default_version")
                 So(monitor.Cells[0][0].Value, ShouldEqual, "testVersion1")
         })
 }