Remove base::Value::CreateNullValue

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 45 matching lines @@
     BOOLEAN,
     INTEGER,
     DOUBLE,
     STRING,
     BINARY,
     DICTIONARY,
     LIST
     // Note: Do not add more types. See the file-level comment above for why.
   };
 
-  static std::unique_ptr<Value> CreateNullValue();
-
   // For situations where you want to keep ownership of your buffer, this
   // factory method creates a new BinaryValue by copying the contents of the
   // buffer that's passed in.
   // DEPRECATED, use MakeUnique<Value>(const std::vector<char>&) instead.
   // TODO(crbug.com/646113): Delete this and migrate callsites.
   static std::unique_ptr<BinaryValue> CreateWithCopiedBuffer(const char* buffer,
                                                              size_t size);
 
   Value(const Value& that);
   Value(Value&& that) noexcept;
@@ skipping 93 matching lines @@
   BASE_EXPORT friend bool operator>(const Value& lhs, const Value& rhs);
   BASE_EXPORT friend bool operator<=(const Value& lhs, const Value& rhs);
   BASE_EXPORT friend bool operator>=(const Value& lhs, const Value& rhs);
 
   // Compares if two Value objects have equal contents.
   // DEPRECATED, use operator==(const Value& lhs, const Value& rhs) instead.
   // TODO(crbug.com/646113): Delete this and migrate callsites.
   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().
+  // NULLs are considered equal but different from Value(Value::Type::NONE).
   // DEPRECATED, use operator==(const Value& lhs, const Value& rhs) instead.
   // TODO(crbug.com/646113): Delete this and migrate callsites.
   static bool Equals(const Value* a, const Value* b);
 
  protected:
   // TODO(crbug.com/646113): Make these private once DictionaryValue and
   // ListValue are properly inlined.
   Type type_;
 
   union {
@@ skipping 340 matching lines @@
   return out << static_cast<const Value&>(value);
 }
 
 // Stream operator so that enum class Types can be used in log statements.
 BASE_EXPORT std::ostream& operator<<(std::ostream& out,
                                      const Value::Type& type);
 
 }  // namespace base
 
 #endif  // BASE_VALUES_H_