Update from https://crrev.com/329939

base/values.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.
 
 // This file specifies a recursive data storage class called Value intended for
 // storing settings and other persistable data.
 //
 // A Value represents something that can be stored in JSON or passed to/from
 // JavaScript. As such, it is NOT a generalized variant type, since only the
 // types supported by JavaScript/JSON are supported.
@@ skipping 46 matching lines @@
     TYPE_DOUBLE,
     TYPE_STRING,
     TYPE_BINARY,
     TYPE_DICTIONARY,
     TYPE_LIST
     // Note: Do not add more types. See the file-level comment above for why.
   };
 
   virtual ~Value();
 
-  static Value* CreateNullValue();
+  static scoped_ptr<Value> CreateNullValue();
 
   // Returns the type of the value stored by the current Value object.
   // Each type will be implemented by only one subclass of Value, so it's
   // safe to use the Type to determine whether you can cast from
   // Value* to (Implementing Class)*.  Also, a Value object never changes
   // its type after construction.
   Type GetType() const { return type_; }
 
   // Returns true if the current object represents a given type.
   bool IsType(Type type) const { return type == type_; }
@@ skipping 14 matching lines @@
   virtual bool GetAsDictionary(DictionaryValue** out_value);
   virtual bool GetAsDictionary(const DictionaryValue** out_value) const;
   // Note: Do not add more types. See the file-level comment above for why.
 
   // This creates a deep copy of the entire Value tree, and returns a pointer
   // to the copy.  The caller gets ownership of the copy, of course.
   //
   // Subclasses return their own type directly in their overrides;
   // this works because C++ supports covariant return types.
   virtual Value* DeepCopy() const;
+  // Preferred version of DeepCopy. TODO(estade): remove the above.
+  scoped_ptr<Value> CreateDeepCopy() const;
 
   // Compares if two Value objects have equal contents.
   virtual bool Equals(const Value* other) const;
 
   // Compares if two Value objects have equal contents. Can handle NULLs.
   // NULLs are considered equal but different from Value::CreateNullValue().
   static bool Equals(const Value* a, const Value* b);
 
  protected:
   // These aren't safe for end-users, but they are useful for subclasses.
@@ skipping 249 matching lines @@
     const std::string& key() const { return it_->first; }
     const Value& value() const { return *it_->second; }
 
    private:
     const DictionaryValue& target_;
     ValueMap::const_iterator it_;
   };
 
   // Overridden from Value:
   DictionaryValue* DeepCopy() const override;
+  // Preferred version of DeepCopy. TODO(estade): remove the above.
+  scoped_ptr<DictionaryValue> CreateDeepCopy() const;
   bool Equals(const Value* other) const override;
 
  private:
   ValueMap dictionary_;
 
   DISALLOW_COPY_AND_ASSIGN(DictionaryValue);
 };
 
 // This type of Value represents a list of other Value values.
 class BASE_EXPORT ListValue : public Value {
@@ skipping 12 matching lines @@
 
   // Returns whether the list is empty.
   bool empty() const { return list_.empty(); }
 
   // Sets the list item at the given index to be the Value specified by
   // the value given.  If the index beyond the current end of the list, null
   // Values will be used to pad out the list.
   // Returns true if successful, or false if the index was negative or
   // the value is a null pointer.
   bool Set(size_t index, Value* in_value);
+  // Preferred version of the above. TODO(estade): remove the above.
+  bool Set(size_t index, scoped_ptr<Value> in_value);
 
   // Gets the Value at the given index.  Modifies |out_value| (and returns true)
   // only if the index falls within the current list range.
   // Note that the list always owns the Value passed out via |out_value|.
   // |out_value| is optional and will only be set if non-NULL.
   bool Get(size_t index, const Value** out_value) const;
   bool Get(size_t index, Value** out_value);
 
   // Convenience forms of Get().  Modifies |out_value| (and returns true)
   // only if the index is valid and the Value at that index can be returned
@@ skipping 25 matching lines @@
   // if not found.
   bool Remove(const Value& value, size_t* index);
 
   // Removes the element at |iter|. If |out_value| is NULL, the value will be
   // deleted, otherwise ownership of the value is passed back to the caller.
   // Returns an iterator pointing to the location of the element that
   // followed the erased element.
   iterator Erase(iterator iter, scoped_ptr<Value>* out_value);
 
   // Appends a Value to the end of the list.
+  void Append(scoped_ptr<Value> in_value);
+  // Deprecated version of the above. TODO(estade): remove.
   void Append(Value* in_value);
 
   // Convenience forms of Append.
   void AppendBoolean(bool in_value);
   void AppendInteger(int in_value);
   void AppendDouble(double in_value);
   void AppendString(const std::string& in_value);
   void AppendString(const string16& in_value);
   void AppendStrings(const std::vector<std::string>& in_values);
   void AppendStrings(const std::vector<string16>& in_values);
@@ skipping 21 matching lines @@
 
   const_iterator begin() const { return list_.begin(); }
   const_iterator end() const { return list_.end(); }
 
   // Overridden from Value:
   bool GetAsList(ListValue** out_value) override;
   bool GetAsList(const ListValue** out_value) const override;
   ListValue* DeepCopy() const override;
   bool Equals(const Value* other) const override;
 
+  // Preferred version of DeepCopy. TODO(estade): remove DeepCopy.
+  scoped_ptr<ListValue> CreateDeepCopy() const;
+
  private:
   ValueVector list_;
 
   DISALLOW_COPY_AND_ASSIGN(ListValue);
 };
 
 // This interface is implemented by classes that know how to serialize
 // Value objects.
 class BASE_EXPORT ValueSerializer {
  public:
@@ skipping 39 matching lines @@
 }
 
 BASE_EXPORT inline std::ostream& operator<<(std::ostream& out,
                                             const ListValue& value) {
   return out << static_cast<const Value&>(value);
 }
 
 }  // namespace base
 
 #endif  // BASE_VALUES_H_