Migrate content/ files to histogram_macros.h includes.

content/renderer/media/webrtc/stun_field_trial.cc

 // 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.
 
 #include "content/renderer/media/webrtc/stun_field_trial.h"
 
 #include <math.h>
 
 #include "base/bind.h"
 #include "base/location.h"
 #include "base/logging.h"
 #include "base/macros.h"
-#include "base/metrics/histogram.h"
+#include "base/metrics/histogram_macros.h"
 #include "base/rand_util.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_split.h"
 #include "base/strings/stringprintf.h"
 #include "base/time/time.h"
 #include "third_party/webrtc/base/asyncpacketsocket.h"
 #include "third_party/webrtc/base/asyncresolverinterface.h"
 #include "third_party/webrtc/base/ipaddress.h"
 #include "third_party/webrtc/base/network.h"
 #include "third_party/webrtc/base/socketaddress.h"
@@ skipping 280 matching lines @@
 void StunProberTrial::OnTimer() {
   DCHECK(thread_checker_.CalledOnValidThread());
   probers_[started_probers_]->Start(this);
   started_probers_++;
 
   if (started_probers_ == total_probers_)
     timer_.Stop();
 }
 
 }  // namespace content