diff -r 000000000000 -r 6474c204b198 xpcom/ds/TimeStamp_windows.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/xpcom/ds/TimeStamp_windows.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,61 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et cindent: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_TimeStamp_windows_h
+#define mozilla_TimeStamp_windows_h
+
+namespace mozilla {
+
+class TimeStamp;
+
+class TimeStampValue
+{
+  friend struct IPC::ParamTraits<mozilla::TimeStampValue>;
+  friend class TimeStamp;
+  friend void StartupTimelineRecordExternal(int, uint64_t);
+
+  // Both QPC and GTC are kept in [mt] units.
+  uint64_t mGTC;
+  uint64_t mQPC;
+  bool mHasQPC;
+  bool mIsNull;
+
+  TimeStampValue(uint64_t GTC, uint64_t QPC, bool hasQPC);
+
+  uint64_t CheckQPC(const TimeStampValue &aOther) const;
+
+  struct _SomethingVeryRandomHere;
+  MOZ_CONSTEXPR TimeStampValue(_SomethingVeryRandomHere* nullValue)
+    : mGTC(0), mQPC(0), mHasQPC(false), mIsNull(true) {}
+
+
+public:
+  uint64_t operator-(const TimeStampValue &aOther) const;
+
+  TimeStampValue operator+(const int64_t aOther) const
+    { return TimeStampValue(mGTC + aOther, mQPC + aOther, mHasQPC); }
+  TimeStampValue operator-(const int64_t aOther) const
+    { return TimeStampValue(mGTC - aOther, mQPC - aOther, mHasQPC); }
+  TimeStampValue& operator+=(const int64_t aOther);
+  TimeStampValue& operator-=(const int64_t aOther);
+
+  bool operator<(const TimeStampValue &aOther) const
+    { return int64_t(*this - aOther) < 0; }
+  bool operator>(const TimeStampValue &aOther) const
+    { return int64_t(*this - aOther) > 0; }
+  bool operator<=(const TimeStampValue &aOther) const
+    { return int64_t(*this - aOther) <= 0; }
+  bool operator>=(const TimeStampValue &aOther) const
+    { return int64_t(*this - aOther) >= 0; }
+  bool operator==(const TimeStampValue &aOther) const
+    { return int64_t(*this - aOther) == 0; }
+  bool operator!=(const TimeStampValue &aOther) const
+    { return int64_t(*this - aOther) != 0; }
+};
+
+}
+
+#endif /* mozilla_TimeStamp_h */