Update SupportsUserData uses with unique_ptr.

chrome/browser/supervised_user/supervised_user_interstitial.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/supervised_user/supervised_user_interstitial.h"
 
 #include <stddef.h>
 
 #include "base/memory/weak_ptr.h"
 #include "base/metrics/histogram_macros.h"
@@ skipping 35 matching lines @@
 #include "chrome/browser/ui/tabs/tab_strip_model.h"
 #endif
 
 using content::BrowserThread;
 using content::WebContents;
 
 namespace {
 
 class TabCloser : public content::WebContentsUserData<TabCloser> {
  public:
+  ~TabCloser() override {}
+
   static void MaybeClose(WebContents* web_contents) {
     DCHECK(web_contents);
 
     // Close the tab only if there is a browser for it (which is not the case
     // for example in a <webview>).
 #if !defined(OS_ANDROID)
     if (!chrome::FindBrowserWithWebContents(web_contents))
       return;
 #endif
     TabCloser::CreateForWebContents(web_contents);
   }
 
  private:
   friend class content::WebContentsUserData<TabCloser>;
 
   explicit TabCloser(WebContents* web_contents)
       : web_contents_(web_contents), weak_ptr_factory_(this) {
     BrowserThread::PostTask(
         BrowserThread::UI,
         FROM_HERE,
         base::Bind(&TabCloser::CloseTabImpl, weak_ptr_factory_.GetWeakPtr()));
   }
-  ~TabCloser() override {}
 
   void CloseTabImpl() {
     // On Android, FindBrowserWithWebContents and TabStripModel don't exist.
 #if !defined(OS_ANDROID)
     Browser* browser = chrome::FindBrowserWithWebContents(web_contents_);
     DCHECK(browser);
     TabStripModel* tab_strip = browser->tab_strip_model();
     DCHECK_NE(TabStripModel::kNoTab,
               tab_strip->GetIndexOfWebContents(web_contents_));
     if (tab_strip->count() <= 1) {
@@ skipping 259 matching lines @@
       SupervisedUserServiceFactory::GetForProfile(profile_);
   supervised_user_service->RemoveObserver(this);
 
   if (!callback_.is_null())
     callback_.Run(continue_request);
 
   // After this, the WebContents may be destroyed. Make sure we don't try to use
   // it again.
   web_contents_ = nullptr;
 }