components/metrics: Add runtime memory leak detector

components/metrics/leak_detector/leak_detector.h

+// Copyright 2015 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 COMPONENTS_METRICS_LEAK_DETECTOR_LEAK_DETECTOR_H_
+#define COMPONENTS_METRICS_LEAK_DETECTOR_LEAK_DETECTOR_H_
+
+namespace leak_detector {
+
+// The top level leak detector is a singleton instance. Implement it as a
+// namespace with init/shutdown functions rather than as a class with static
+// member functions.
+
+void Initialize();
+void Shutdown();
+
+bool IsInitialized();
+
+}  // namespace leak_detector
+
+#endif  // COMPONENTS_METRICS_LEAK_DETECTOR_LEAK_DETECTOR_H_