Ensure task queues delete closures in task queue context.

Bug: webrtc:14449
Change-Id: I90d09d35398c1f8817701662f51cbc6a684a2fe0
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/275773
Commit-Queue: Markus Handell <handellm@webrtc.org>
Reviewed-by: Tomas Gunnarsson <tommi@webrtc.org>
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Reviewed-by: Danil Chapovalov <danilchap@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#38917}
diff --git a/rtc_base/task_queue_stdlib_unittest.cc b/rtc_base/task_queue_stdlib_unittest.cc
new file mode 100644
index 0000000..0654e97
--- /dev/null
+++ b/rtc_base/task_queue_stdlib_unittest.cc
@@ -0,0 +1,29 @@
+/*
+ *  Copyright 2022 The WebRTC Project Authors. All rights reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "rtc_base/task_queue_stdlib.h"
+
+#include "api/task_queue/task_queue_test.h"
+#include "test/gtest.h"
+
+namespace webrtc {
+namespace {
+
+std::unique_ptr<TaskQueueFactory> CreateTaskQueueFactory(
+    const webrtc::FieldTrialsView*) {
+  return CreateTaskQueueStdlibFactory();
+}
+
+INSTANTIATE_TEST_SUITE_P(TaskQueueStdlib,
+                         TaskQueueTest,
+                         ::testing::Values(CreateTaskQueueFactory));
+
+}  // namespace
+}  // namespace webrtc