diff -r 000000000000 -r 6474c204b198 security/sandbox/chromium/base/at_exit.cc
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/security/sandbox/chromium/base/at_exit.cc	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,82 @@
+// 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"
+#include "base/callback.h"
+#include "base/logging.h"
+
+namespace base {
+
+// Keep a stack of registered AtExitManagers.  We always operate on the most
+// recent, and we should never have more than one outside of testing (for a
+// statically linked version of this library).  Testing may use the shadow
+// version of the constructor, and if we are building a dynamic library we may
+// end up with multiple AtExitManagers on the same process.  We don't protect
+// this for thread-safe access, since it will only be modified in testing.
+static AtExitManager* g_top_manager = NULL;
+
+AtExitManager::AtExitManager() : next_manager_(g_top_manager) {
+// If multiple modules instantiate AtExitManagers they'll end up living in this
+// module... they have to coexist.
+#if !defined(COMPONENT_BUILD)
+  DCHECK(!g_top_manager);
+#endif
+  g_top_manager = this;
+}
+
+AtExitManager::~AtExitManager() {
+  if (!g_top_manager) {
+    NOTREACHED() << "Tried to ~AtExitManager without an AtExitManager";
+    return;
+  }
+  DCHECK_EQ(this, g_top_manager);
+
+  ProcessCallbacksNow();
+  g_top_manager = next_manager_;
+}
+
+// static
+void AtExitManager::RegisterCallback(AtExitCallbackType func, void* param) {
+  DCHECK(func);
+  RegisterTask(base::Bind(func, param));
+}
+
+// static
+void AtExitManager::RegisterTask(base::Closure task) {
+  if (!g_top_manager) {
+    NOTREACHED() << "Tried to RegisterCallback without an AtExitManager";
+    return;
+  }
+
+  AutoLock lock(g_top_manager->lock_);
+  g_top_manager->stack_.push(task);
+}
+
+// static
+void AtExitManager::ProcessCallbacksNow() {
+  if (!g_top_manager) {
+    NOTREACHED() << "Tried to ProcessCallbacksNow without an AtExitManager";
+    return;
+  }
+
+  AutoLock lock(g_top_manager->lock_);
+
+  while (!g_top_manager->stack_.empty()) {
+    base::Closure task = g_top_manager->stack_.top();
+    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;
+}
+
+}  // namespace base