[iOS] Upstream //ios/chrome/browser/memory

ios/chrome/browser/memory/memory_metrics.h

+// Copyright 2014 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 IOS_CHROME_BROWSER_MEMORY_MEMORY_METRICS_H_
+#define IOS_CHROME_BROWSER_MEMORY_MEMORY_METRICS_H_
+
+#include "base/basictypes.h"
+
+namespace memory_util {
+// "Physical Free" memory metric. This corresponds to the "Physical Memory Free"
+// value reported by the Memory Monitor in Instruments.
+uint64 GetFreePhysicalBytes();
+
+// "Real Memory Used" memory metric. This corresponds to the "Real Memory" value
+// reported for the app by the Memory Monitor in Instruments.
+uint64 GetRealMemoryUsedInBytes();
+
+// "Xcode Gauge" memory metric. This corresponds to the "Memory" value reported
+// for the app by the Debug Navigator in Xcode. Only supported in iOS 7 and
+// later.
+uint64 GetInternalVMBytes();
+
+// "Dirty VM" memory metric. This corresponds to the "Dirty Size" value reported
+// for the app by the VM Tracker in Instruments.
+uint64 GetDirtyVMBytes();
+}  // namespace memory_util
+
+#endif  // IOS_CHROME_BROWSER_MEMORY_MEMORY_METRICS_H_