For unit tests, track additions to AtExitManager and warn.

base/at_exit.cc

 // Copyright (c) 2011 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.
 
 #include "base/at_exit.h"
 
 #include <stddef.h>
 #include <ostream>
 
 #include "base/bind.h"
@@ skipping 61 matching lines @@
     task.Run();
     g_top_manager->stack_.pop();
   }
 }
 
 AtExitManager::AtExitManager(bool shadow) : next_manager_(g_top_manager) {
   DCHECK(shadow || !g_top_manager);
   g_top_manager = this;
 }
 
+// static
+AtExitManager* AtExitManager::current() {
+  return g_top_manager;
+}
+
+size_t AtExitManager::CallbackStackSize() const {
+  return stack_.size();
+}
+
 }  // namespace base