Modify ThreadChecker and NonThreadSafe so that their functionality is

base/threading/non_thread_safe_impl.cc

Index: base/threading/non_thread_safe_impl.cc
diff --git a/base/threading/non_thread_safe_impl.cc b/base/threading/non_thread_safe_impl.cc
new file mode 100644
index 0000000000000000000000000000000000000000..f9c18c2d147aadc5ae66d21b38f931fcabc8507b
--- /dev/null
+++ b/base/threading/non_thread_safe_impl.cc
@@ -0,0 +1,23 @@
+// 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/threading/non_thread_safe_impl.h"
+
+#include "base/logging.h"
+
+namespace base {
+
+NonThreadSafeImpl::~NonThreadSafeImpl() {
+  DCHECK(CalledOnValidThread());
+}
+
+bool NonThreadSafeImpl::CalledOnValidThread() const {
+  return thread_checker_.CalledOnValidThread();
+}
+
+void NonThreadSafeImpl::DetachFromThread() {
+  thread_checker_.DetachFromThread();
+}
+
+}  // namespace base