From 9b028ececfae32293ca26bd3303e1fa27c098e92 Mon Sep 17 00:00:00 2001
From: Chris Kennelly <ckennelly@google.com>
Date: Mon, 31 Oct 2022 17:05:27 -0700
Subject: [PATCH] Internal change

PiperOrigin-RevId: 485184009
---
 src/google/protobuf/arena.h | 14 +-------------
 1 file changed, 1 insertion(+), 13 deletions(-)

diff --git a/src/google/protobuf/arena.h b/src/google/protobuf/arena.h
index d3dec65170..255b98fe47 100644
--- a/src/google/protobuf/arena.h
+++ b/src/google/protobuf/arena.h
@@ -148,19 +148,9 @@ struct ArenaOptions {
         initial_block(nullptr),
         initial_block_size(0),
         block_alloc(nullptr),
-        block_dealloc(nullptr),
-        make_metrics_collector(nullptr) {}
+        block_dealloc(nullptr) {}
 
  private:
-  // If make_metrics_collector is not nullptr, it will be called at Arena init
-  // time. It may return a pointer to a collector instance that will be notified
-  // of interesting events related to the arena.
-  internal::ArenaMetricsCollector* (*make_metrics_collector)();
-
-  internal::ArenaMetricsCollector* MetricsCollector() const {
-    return make_metrics_collector ? (*make_metrics_collector)() : nullptr;
-  }
-
   internal::AllocationPolicy AllocationPolicy() const {
     internal::AllocationPolicy res;
     res.start_block_size = start_block_size;
@@ -170,8 +160,6 @@ struct ArenaOptions {
     return res;
   }
 
-  friend void arena_metrics::EnableArenaMetrics(ArenaOptions*);
-
   friend class Arena;
   friend class ArenaOptionsTestFriend;
 };