Convert //ios from scoped_ptr to std::unique_ptr.

ios/chrome/browser/signin/gaia_auth_fetcher_ios.h

 // Copyright 2015 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.
 
 #ifndef IOS_CHROME_BROWSER_SIGNIN_GAIA_AUTH_FETCHER_IOS_H_
 #define IOS_CHROME_BROWSER_SIGNIN_GAIA_AUTH_FETCHER_IOS_H_
 
+#include <memory>
+
 #include "base/macros.h"
-#include "base/memory/scoped_ptr.h"
 #include "google_apis/gaia/gaia_auth_fetcher.h"
 
 class GaiaAuthFetcherIOSBridge;
 
 namespace web {
 class BrowserState;
 }
 
 // Specialization of GaiaAuthFetcher on iOS.
 //
@@ skipping 30 matching lines @@
   void CreateAndStartGaiaFetcher(const std::string& body,
                                  const std::string& headers,
                                  const GURL& gaia_gurl,
                                  int load_flags) override;
   void FetchComplete(const GURL& url,
                      const std::string& data,
                      const net::ResponseCookies& cookies,
                      const net::URLRequestStatus& status,
                      int response_code);
 
-  scoped_ptr<GaiaAuthFetcherIOSBridge> bridge_;
+  std::unique_ptr<GaiaAuthFetcherIOSBridge> bridge_;
   web::BrowserState* browser_state_;
 
   DISALLOW_COPY_AND_ASSIGN(GaiaAuthFetcherIOS);
 };
 
 #endif  // IOS_CHROME_BROWSER_SIGNIN_GAIA_AUTH_FETCHER_IOS_H_