Update SupportsUserData uses with unique_ptr.

chrome/browser/metrics/desktop_session_duration/desktop_session_duration_observer.cc

 // 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 "chrome/browser/metrics/desktop_session_duration/desktop_session_duration_observer.h"
 
+#include "base/memory/ptr_util.h"
 #include "chrome/browser/metrics/desktop_session_duration/desktop_session_duration_tracker.h"
 #include "content/public/browser/render_view_host.h"
 
 DEFINE_WEB_CONTENTS_USER_DATA_KEY(metrics::DesktopSessionDurationObserver);
 
 namespace metrics {
 
 DesktopSessionDurationObserver::DesktopSessionDurationObserver(
     content::WebContents* web_contents,
     DesktopSessionDurationTracker* service)
     : content::WebContentsObserver(web_contents), service_(service) {
   RegisterInputEventObserver(web_contents->GetRenderViewHost());
 }
 
 DesktopSessionDurationObserver::~DesktopSessionDurationObserver() {}
 
 // static
 DesktopSessionDurationObserver*
 DesktopSessionDurationObserver::CreateForWebContents(
     content::WebContents* web_contents) {
   DCHECK(web_contents);
 
   if (!DesktopSessionDurationTracker::IsInitialized())
     return nullptr;
 
   DesktopSessionDurationObserver* observer = FromWebContents(web_contents);
   if (!observer) {
     observer = new DesktopSessionDurationObserver(
         web_contents, DesktopSessionDurationTracker::Get());
-    web_contents->SetUserData(UserDataKey(), observer);
+    web_contents->SetUserData(UserDataKey(), base::WrapUnique(observer));
   }
   return observer;
 }
 
 void DesktopSessionDurationObserver::RegisterInputEventObserver(
     content::RenderViewHost* host) {
   if (host != nullptr)
     host->GetWidget()->AddInputEventObserver(this);
 }
 
 void DesktopSessionDurationObserver::UnregisterInputEventObserver(
     content::RenderViewHost* host) {
   if (host != nullptr)
     host->GetWidget()->RemoveInputEventObserver(this);
 }
 
 void DesktopSessionDurationObserver::OnInputEvent(
     const blink::WebInputEvent& event) {
   service_->OnUserEvent();
 }
 
 void DesktopSessionDurationObserver::RenderViewHostChanged(
     content::RenderViewHost* old_host,
     content::RenderViewHost* new_host) {
   UnregisterInputEventObserver(old_host);
   RegisterInputEventObserver(new_host);
 }
 
 }  // namespace metrics