Re-write many calls to WrapUnique() with MakeUnique()

ios/chrome/browser/metrics/ios_chrome_metrics_services_manager_client.mm

 // 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 "ios/chrome/browser/metrics/ios_chrome_metrics_services_manager_client.h"
 
 #include "base/command_line.h"
 #include "base/logging.h"
 #include "base/memory/ptr_util.h"
 #include "components/metrics/enabled_state_provider.h"
@@ skipping 39 matching lines @@
       local_state_(local_state) {
   DCHECK(local_state);
 }
 
 IOSChromeMetricsServicesManagerClient::
     ~IOSChromeMetricsServicesManagerClient() = default;
 
 std::unique_ptr<rappor::RapporService>
 IOSChromeMetricsServicesManagerClient::CreateRapporService() {
   DCHECK(thread_checker_.CalledOnValidThread());
-  return base::WrapUnique(new rappor::RapporService(
-      local_state_, base::Bind(&::IsOffTheRecordSessionActive)));
+  return base::MakeUnique<rappor::RapporService>(
+      local_state_, base::Bind(&::IsOffTheRecordSessionActive));
 }
 
 std::unique_ptr<variations::VariationsService>
 IOSChromeMetricsServicesManagerClient::CreateVariationsService() {
   DCHECK(thread_checker_.CalledOnValidThread());
 
   // NOTE: On iOS, disabling background networking is not supported, so pass in
   // a dummy value for the name of the switch that disables background
   // networking.
   return variations::VariationsService::Create(
@@ skipping 33 matching lines @@
 IOSChromeMetricsServicesManagerClient::GetMetricsStateManager() {
   DCHECK(thread_checker_.CalledOnValidThread());
   if (!metrics_state_manager_) {
     metrics_state_manager_ = metrics::MetricsStateManager::Create(
         local_state_, enabled_state_provider_.get(),
         base::Bind(&PostStoreMetricsClientInfo),
         base::Bind(&LoadMetricsClientInfo));
   }
   return metrics_state_manager_.get();
 }