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

ios/chrome/test/ios_chrome_scoped_testing_chrome_browser_provider.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_TEST_IOS_CHROME_SCOPED_TESTING_CHROME_BROWSER_PROVIDER_H_
 #define IOS_CHROME_TEST_IOS_CHROME_SCOPED_TESTING_CHROME_BROWSER_PROVIDER_H_
 
+#include <memory>
+
 #include "base/macros.h"
-#include "base/memory/scoped_ptr.h"
 
 namespace ios {
 class ChromeBrowserProvider;
 }
 
 // Helper class to temporarily set up a ChromeBrowserProvider and restore
 // the previous one on teardown.
 class IOSChromeScopedTestingChromeBrowserProvider {
  public:
   explicit IOSChromeScopedTestingChromeBrowserProvider(
-      scoped_ptr<ios::ChromeBrowserProvider> chrome_browser_provider);
+      std::unique_ptr<ios::ChromeBrowserProvider> chrome_browser_provider);
   ~IOSChromeScopedTestingChromeBrowserProvider();
 
  private:
-  scoped_ptr<ios::ChromeBrowserProvider> chrome_browser_provider_;
+  std::unique_ptr<ios::ChromeBrowserProvider> chrome_browser_provider_;
   ios::ChromeBrowserProvider* original_chrome_browser_provider_;
 
   DISALLOW_COPY_AND_ASSIGN(IOSChromeScopedTestingChromeBrowserProvider);
 };
 
 #endif  // IOS_CHROME_TEST_IOS_CHROME_SCOPED_TESTING_CHROME_BROWSER_PROVIDER_H_