chrome://profiler infrastructure uses base time types.

base/profiler/tracked_time.h

-// Copyright (c) 2012 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 BASE_PROFILER_TRACKED_TIME_H_
-#define BASE_PROFILER_TRACKED_TIME_H_
-
-#include <stdint.h>
-
-#include "base/base_export.h"
-#include "base/time/time.h"
-
-namespace tracked_objects {
-
-//------------------------------------------------------------------------------
-
-// TimeTicks maintains a wasteful 64 bits of data (we need less than 32), and on
-// windows, a 64 bit timer is expensive to even obtain. We use a simple
-// millisecond counter for most of our time values, as well as millisecond units
-// of duration between those values.  This means we can only handle durations
-// up to 49 days (range), or 24 days (non-negative time durations).
-// We only define enough methods to service the needs of the tracking classes,
-// and our interfaces are modeled after what TimeTicks and TimeDelta use (so we
-// can swap them into place if we want to use the "real" classes).
-
-class BASE_EXPORT Duration {  // Similar to base::TimeDelta.
- public:
-  Duration();
-
-  Duration& operator+=(const Duration& other);
-  Duration operator+(const Duration& other) const;
-
-  bool operator==(const Duration& other) const;
-  bool operator!=(const Duration& other) const;
-  bool operator>(const Duration& other) const;
-
-  static Duration FromMilliseconds(int ms);
-
-  int32_t InMilliseconds() const;
-
- private:
-  friend class TrackedTime;
-  explicit Duration(int32_t duration);
-
-  // Internal time is stored directly in milliseconds.
-  int32_t ms_;
-};
-
-class BASE_EXPORT TrackedTime {  // Similar to base::TimeTicks.
- public:
-  TrackedTime();
-  explicit TrackedTime(const base::TimeTicks& time);
-
-  static TrackedTime Now();
-  Duration operator-(const TrackedTime& other) const;
-  TrackedTime operator+(const Duration& other) const;
-  bool is_null() const;
-
-  static TrackedTime FromMilliseconds(int32_t ms) { return TrackedTime(ms); }
-
- private:
-  friend class Duration;
-  explicit TrackedTime(int32_t ms);
-
-  // Internal duration is stored directly in milliseconds.
-  uint32_t ms_;
-};
-
-}  // namespace tracked_objects
-
-#endif  // BASE_PROFILER_TRACKED_TIME_H_