Deprecate NonThreadSafe in remoting in favor of SequenceChecker.

remoting/host/host_window.cc

Index: remoting/host/host_window.cc
diff --git a/remoting/host/host_window.cc b/remoting/host/host_window.cc
new file mode 100644
index 0000000000000000000000000000000000000000..0b2be09c77d663007e599bc75c1834e811762b7e
--- /dev/null
+++ b/remoting/host/host_window.cc
@@ -0,0 +1,13 @@
+// Copyright 2017 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 "remoting/host/host_window.h"
+
+namespace remoting {
+
+HostWindow::~HostWindow() {
+  DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
+}
+
+}  // namespace remoting