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

ios/chrome/browser/ios_chrome_main_parts.mm

 // 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.
 
 #include "ios/chrome/browser/ios_chrome_main_parts.h"
 
 #include "base/base_switches.h"
 #include "base/feature_list.h"
 #include "base/files/file_path.h"
 #include "base/logging.h"
@@ skipping 89 matching lines @@
   local_state_ = application_context_->GetLocalState();
   DCHECK(local_state_);
 
   flags_ui::PrefServiceFlagsStorage flags_storage(
       application_context_->GetLocalState());
   ConvertFlagsToSwitches(&flags_storage,
                          base::CommandLine::ForCurrentProcess());
 
   // Initialize tracking synchronizer system.
   tracking_synchronizer_ = new metrics::TrackingSynchronizer(
-      base::WrapUnique(new base::DefaultTickClock()),
+      base::MakeUnique<base::DefaultTickClock>(),
       base::Bind(&metrics::IOSTrackingSynchronizerDelegate::Create));
 
   // Now the command line has been mutated based on about:flags, we can setup
   // metrics and initialize field trials that are needed by IOSChromeIOThread's
   // initialization which happens in ApplicationContext:PreCreateThreads.
   SetUpMetricsAndFieldTrials();
 
   // Initialize FieldTrialSynchronizer system.
   field_trial_synchronizer_.reset(new ios::FieldTrialSynchronizer);
 
@@ skipping 135 matching lines @@
 
 void IOSChromeMainParts::StartMetricsRecording() {
   bool wifiOnly = local_state_->GetBoolean(prefs::kMetricsReportingWifiOnly);
   bool isConnectionCellular = net::NetworkChangeNotifier::IsConnectionCellular(
       net::NetworkChangeNotifier::GetConnectionType());
   bool mayUpload = !wifiOnly || !isConnectionCellular;
 
   application_context_->GetMetricsServicesManager()->UpdateUploadPermissions(
       mayUpload);
 }