Convert //base to use std::unique_ptr

base/metrics/field_trial.h

 // Copyright (c) 2012 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.
 
 // FieldTrial is a class for handling details of statistical experiments
 // performed by actual users in the field (i.e., in a shipped or beta product).
 // All code is called exclusively on the UI thread currently.
 //
 // The simplest example is an experiment to see whether one of two options
 // produces "better" results across our user population.  In that scenario, UMA
@@ skipping 496 matching lines @@
   static bool used_without_global_;
 
   // Lock for access to registered_.
   base::Lock lock_;
   RegistrationMap registered_;
 
   std::map<std::string, std::string> seen_states_;
 
   // Entropy provider to be used for one-time randomized field trials. If NULL,
   // one-time randomization is not supported.
-  scoped_ptr<const FieldTrial::EntropyProvider> entropy_provider_;
+  std::unique_ptr<const FieldTrial::EntropyProvider> entropy_provider_;
 
   // List of observers to be notified when a group is selected for a FieldTrial.
   scoped_refptr<ObserverListThreadSafe<Observer> > observer_list_;
 
   DISALLOW_COPY_AND_ASSIGN(FieldTrialList);
 };
 
 }  // namespace base
 
 #endif  // BASE_METRICS_FIELD_TRIAL_H_