Migrate chrome/browser files to histogram_macros.h includes.

chrome/browser/prefs/pref_metrics_service.cc

 // Copyright 2013 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 "chrome/browser/prefs/pref_metrics_service.h"
 
 #include <stddef.h>
 
 #include "base/bind.h"
 #include "base/command_line.h"
-#include "base/metrics/histogram.h"
+#include "base/metrics/histogram_macros.h"
 #include "base/strings/string_number_conversions.h"
 #include "build/build_config.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/prefs/pref_service_syncable_util.h"
 #include "chrome/browser/prefs/session_startup_pref.h"
 #include "chrome/browser/profiles/incognito_helpers.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/search_engines/template_url_service_factory.h"
 #include "chrome/browser/ui/tabs/pinned_tab_codec.h"
 #include "chrome/common/pref_names.h"
@@ skipping 250 matching lines @@
 }
 
 bool PrefMetricsService::Factory::ServiceIsNULLWhileTesting() const {
   return false;
 }
 
 content::BrowserContext* PrefMetricsService::Factory::GetBrowserContextToUse(
     content::BrowserContext* context) const {
   return chrome::GetBrowserContextRedirectedInIncognito(context);
 }