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diff --git a/chromium/base/util/ranges/functional.h b/chromium/base/util/ranges/functional.h
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+++ b/chromium/base/util/ranges/functional.h
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+// Copyright 2020 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_UTIL_RANGES_FUNCTIONAL_H_
+#define BASE_UTIL_RANGES_FUNCTIONAL_H_
+
+#include <functional>
+#include <type_traits>
+#include <utility>
+
+namespace util {
+
+// Implementation of C++20's std::identity.
+//
+// Reference:
+// - https://en.cppreference.com/w/cpp/utility/functional/identity
+// - https://wg21.link/func.identity
+struct identity {
+  template <typename T>
+  constexpr T&& operator()(T&& t) const noexcept {
+    return std::forward<T>(t);
+  }
+
+  using is_transparent = void;
+};
+
+// Minimal implementation of C++17's std::invoke. Based on implementation
+// referenced in original std::invoke proposal.
+//
+// Note: Unlike C++20's std::invoke this implementation is not constexpr. A
+// constexpr version can be added in the future, but it won't be as concise,
+// since std::mem_fn is not constexpr prior to C++20.
+//
+// References:
+// - https://wg21.link/n4169#implementability
+// - https://en.cppreference.com/w/cpp/utility/functional/invoke
+// - https://wg21.link/func.invoke
+template <typename Functor,
+          typename... Args,
+          std::enable_if_t<
+              std::is_member_pointer<std::decay_t<Functor>>::value>* = nullptr>
+decltype(auto) invoke(Functor&& f, Args&&... args) {
+  return std::mem_fn(f)(std::forward<Args>(args)...);
+}
+
+template <typename Functor,
+          typename... Args,
+          std::enable_if_t<
+              !std::is_member_pointer<std::decay_t<Functor>>::value>* = nullptr>
+decltype(auto) invoke(Functor&& f, Args&&... args) {
+  return std::forward<Functor>(f)(std::forward<Args>(args)...);
+}
+
+// Simplified implementations of C++20's std::ranges comparison function
+// objects. As opposed to the std::ranges implementation, these versions do not
+// constrain the passed-in types.
+//
+// Reference: https://wg21.link/range.cmp
+namespace ranges {
+using equal_to = std::equal_to<>;
+using not_equal_to = std::not_equal_to<>;
+using greater = std::greater<>;
+using less = std::less<>;
+using greater_equal = std::greater_equal<>;
+using less_equal = std::less_equal<>;
+}  // namespace ranges
+
+}  // namespace util
+
+#endif  // BASE_UTIL_RANGES_FUNCTIONAL_H_