SigninStatusMetricsProvider factory returns a std::unique_ptr<>.

chrome/browser/metrics/chrome_metrics_service_client.cc

 // Copyright 2014 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/metrics/chrome_metrics_service_client.h"
 
 #include <stddef.h>
 
 #include <utility>
 #include <vector>
@@ skipping 666 matching lines @@
   // recorded yet.
   if (metrics::GetMetricsReportingDefaultState(local_state) ==
       metrics::EnableMetricsDefault::DEFAULT_UNKNOWN) {
     metrics::RecordMetricsReportingDefaultState(
         local_state, metrics::EnableMetricsDefault::OPT_OUT);
   }
 #endif  // defined(OS_CHROMEOS)
 
 #if !defined(OS_CHROMEOS)
   metrics_service_->RegisterMetricsProvider(
-      std::unique_ptr<metrics::MetricsProvider>(
-          SigninStatusMetricsProvider::CreateInstance(base::WrapUnique(
-              new ChromeSigninStatusMetricsProviderDelegate))));
+      SigninStatusMetricsProvider::CreateInstance(
+          base::WrapUnique(new ChromeSigninStatusMetricsProviderDelegate)));
 #endif  // !defined(OS_CHROMEOS)
 
   metrics_service_->RegisterMetricsProvider(
       std::unique_ptr<metrics::MetricsProvider>(
           new syncer::DeviceCountMetricsProvider(base::Bind(
               &browser_sync::ChromeSyncClient::GetDeviceInfoTrackers))));
 
   metrics_service_->RegisterMetricsProvider(
       std::unique_ptr<metrics::MetricsProvider>(
           new HttpsEngagementMetricsProvider()));
@@ skipping 194 matching lines @@
   }
 }
 
 void ChromeMetricsServiceClient::OnURLOpenedFromOmnibox(OmniboxLog* log) {
   metrics_service_->OnApplicationNotIdle();
 }
 
 bool ChromeMetricsServiceClient::IsUMACellularUploadLogicEnabled() {
   return metrics::IsCellularLogicEnabled();
 }