cc: Use HighResNow as timebase if it is fast and reliable

ui/gfx/frame_time.h

+// Copyright 2013 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 UI_GFX_FRAME_TIME_H
+#define UI_GFX_FRAME_TIME_H
+
+#include "base/time/time.h"
+#include "base/logging.h"
+
+namespace gfx {
+
+// FrameTime::Now() should be used to get timestamps with a timebase that
+// is consistent across the graphics stack.
+class FrameTime {
+ public:
+  static base::TimeTicks Now() {
+    if (TimestampsAreHighRes())
+      return base::TimeTicks::HighResNow();
+    return base::TimeTicks::Now();
+  }
+
+#if defined(OS_WIN)
+  static base::TimeTicks FromQPCValue(LONGLONG qpc_value) {
+    DCHECK(TimestampsAreHighRes());
+    return base::TimeTicks::FromQPCValue(qpc_value);
+  }
+#endif
+
+  static bool TimestampsAreHighRes() {
+    return base::TimeTicks::IsHighResNowFastAndReliable();
+  }
+};
+
+}
+
+#endif // UI_GFX_FRAME_TIME_H