Always set presence/up from go tsmon apps.

appengine/tsmon/middleware.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 tsmon
 
 import (
         "fmt"
         "net/http"
         "strings"
@@ skipping 81 matching lines @@
                 userAgent, ok := c.Request.Header["User-Agent"]
                 if !ok || len(userAgent) == 0 {
                         userAgent = []string{"Unknown"}
                 }
                 ctx := c.Context
                 contentLength := c.Request.ContentLength
                 nrw := newResponseWriter(c.Writer)
                 c.Writer = nrw
                 defer func() {
                         dur := clock.Now(ctx).Sub(started)
-                        metric.UpdatePresenceMetrics(ctx)
                         metric.UpdateServerMetrics(ctx, "/", nrw.Status(), dur,
                                 contentLength, nrw.Size(), userAgent[0])
                 }()
                 next(c)
                 s.flushIfNeeded(ctx, state, settings)
         } else {
                 next(c)
         }
 }
 
@@ skipping 208 matching lines @@
                 }
         }
 
         if err := state.Flush(c, mon); err != nil {
                 return err
         }
 
         state.ResetGlobalCallbackMetrics(c)
         return nil
 }