Implement SequenceChecker, which is a generalization of ThreadChecker

base/test/null_task_runner.cc

+// Copyright (c) 2012 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/test/null_task_runner.h"
+
+namespace base {
+
+NullTaskRunner::NullTaskRunner() {}
+
+NullTaskRunner::~NullTaskRunner() {}
+
+bool NullTaskRunner::PostDelayedTask(
+    const tracked_objects::Location& from_here,
+    const base::Closure& task,
+    base::TimeDelta delay) {
+  return false;
+}
+
+bool NullTaskRunner::PostNonNestableDelayedTask(
+    const tracked_objects::Location& from_here,
+    const base::Closure& task,
+    base::TimeDelta delay) {
+  return false;
+}
+
+bool NullTaskRunner::RunsTasksOnCurrentThread() const {
+  return true;
+}
+
+}  // namespace