Improved check for trivial templates.

tools/clang/plugins/tests/trivial_ctor.h

+// Copyright (c) 2016 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.
+
+#ifndef TRIVIAL_CTOR_H_
+#define TRIVIAL_CTOR_H_
+
+// Mocked for testing:
+namespace std {
+
+template<typename T>
+struct atomic {
+  T i;
+};
+
+typedef atomic<int> atomic_int;
+
+}  // namespace std
+
+struct MySpinLock {
+  MySpinLock();
+  ~MySpinLock();
+  MySpinLock(const MySpinLock&);
+  MySpinLock(MySpinLock&&);
+  std::atomic_int lock_;
+};
+
+#endif  // TRIVIAL_CTOR_H_