SigninStatusMetricsProvider factory returns a std::unique_ptr<>.

chrome/browser/metrics/chrome_metrics_service_client.cc

Index: chrome/browser/metrics/chrome_metrics_service_client.cc
diff --git a/chrome/browser/metrics/chrome_metrics_service_client.cc b/chrome/browser/metrics/chrome_metrics_service_client.cc
index fa618404fe9cbdf83657f32b48140bd05bf1638b..bced9689112ddfebc53943edf3dee70c2c2c2101 100644
--- a/chrome/browser/metrics/chrome_metrics_service_client.cc
+++ b/chrome/browser/metrics/chrome_metrics_service_client.cc
@@ -684,9 +684,8 @@ void ChromeMetricsServiceClient::Initialize() {
 
 #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(