Implement SequenceChecker, which is a generalization of ThreadChecker

base/sequence_checker_impl.cc

Index: base/sequence_checker_impl.cc
diff --git a/base/sequence_checker_impl.cc b/base/sequence_checker_impl.cc
new file mode 100644
index 0000000000000000000000000000000000000000..70a5f3313988a4a836b186ece9cea85fc234b2d3
--- /dev/null
+++ b/base/sequence_checker_impl.cc
@@ -0,0 +1,32 @@
+// 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/sequence_checker_impl.h"
+
+#include "base/sequenced_task_runner.h"
+
+namespace base {
+
+SequenceCheckerImpl::SequenceCheckerImpl(
+    const scoped_refptr<SequencedTaskRunner>& sequenced_task_runner)
+    : sequenced_task_runner_(sequenced_task_runner) {}
+
+SequenceCheckerImpl::~SequenceCheckerImpl() {}
+
+bool SequenceCheckerImpl::CalledInSequence() const {
+  AutoLock auto_lock(lock_);
+  return
+      sequenced_task_runner_.get() ?

[Ryan Sleevi, 2012/12/13 22:49:15]

indent pedantry nit:
return sequenced_task_runner_.get() ?
    x :
    y;

[akalin, 2012/12/18 22:12:19]

Done.

+      sequenced_task_runner_->RunsTasksOnCurrentThread() :
+      thread_checker_.CalledOnValidThread();
+}
+
+void SequenceCheckerImpl::ChangeSequence(
+    const scoped_refptr<SequencedTaskRunner>& sequenced_task_runner) {
+  AutoLock auto_lock(lock_);
+  sequenced_task_runner_ = sequenced_task_runner;
+  thread_checker_.DetachFromThread();
+}
+
+}  // namespace base