Expunge protos_extension_lock entirely

PiperOrigin-RevId: 660444393

protos/BUILD

@@ -54,16 +54,6 @@
 #     ],
 # )
 #
-# cc_library(
-#     name = "protos_extension_lock",
-#     hdrs = ["protos_extension_lock.h"],
-#     copts = UPB_DEFAULT_CPPOPTS,
-#     visibility = ["//visibility:public"],
-#     deps = [
-#         "//hpb:extension_lock",
-#     ],
-# )
-#
 # # Common support code for C++ generated code.
 # cc_library(
 #     name = "generated_protos_support__only_for_generated_code_do_not_use__i_give_permission_to_break_me",

protos/protos_extension_lock.h

@@ -1,16 +0,0 @@
-// Protocol Buffers - Google's data interchange format
-// Copyright 2023 Google LLC.  All rights reserved.
-//
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file or at
-// https://developers.google.com/open-source/licenses/bsd
-
-#ifndef UPB_PROTOS_PROTOS_EXTENSION_LOCK_H_
-#define UPB_PROTOS_PROTOS_EXTENSION_LOCK_H_
-#include "google/protobuf/hpb/extension_lock.h"
-namespace protos::internal {
-using hpb::internal::upb_extension_locker_global;
-using hpb::internal::UpbExtensionLocker;
-using hpb::internal::UpbExtensionUnlocker;
-}  // namespace protos::internal
-#endif