Add missing base/memory/scoped_ptr.h include to base/prefs/writeable_pref_store.h

base/prefs/writeable_pref_store.h

 // 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.
 
 #ifndef BASE_PREFS_WRITEABLE_PREF_STORE_H_
 #define BASE_PREFS_WRITEABLE_PREF_STORE_H_
 
 #include <string>
 
 #include "base/basictypes.h"
+#include "base/memory/scoped_ptr.h"
 #include "base/prefs/pref_store.h"
 
 namespace base {
 class Value;
 }
 
 // A pref store that can be written to as well as read from.
 class BASE_PREFS_EXPORT WriteablePrefStore : public PrefStore {
  public:
   // PrefWriteFlags can be used to change the way a pref will be written to
@@ skipping 39 matching lines @@
                                 uint32 flags) = 0;
 
  protected:
   ~WriteablePrefStore() override {}
 
  private:
   DISALLOW_COPY_AND_ASSIGN(WriteablePrefStore);
 };
 
 #endif  // BASE_PREFS_WRITEABLE_PREF_STORE_H_