Relands: Telemetry: hooks "chrome.gpuBenchmarking.smoothScrollBy" with java on android.

content/browser/renderer_host/smooth_scroll_calculator.h

+// Copyright (c) 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 CONTENT_BROWSER_RENDERER_HOST_SMOOTH_SCROLL_CALCULATOR_H_
+#define CONTENT_BROWSER_RENDERER_HOST_SMOOTH_SCROLL_CALCULATOR_H_
+
+#include "base/time.h"
+
+namespace content {
+
+// An utility class to calculate the delta for smooth scroll gesture
+// events.
+class SmoothScrollCalculator {
+ public:
+  SmoothScrollCalculator();
+  ~SmoothScrollCalculator();
+
+  double GetScrollDelta(base::TimeTicks now, base::TimeDelta desired_interval);
+
+ private:
+  base::TimeTicks last_tick_time_;
+
+  DISALLOW_COPY_AND_ASSIGN(SmoothScrollCalculator);
+};
+
+} // namespace content
+
+#endif  // CONTENT_BROWSER_RENDERER_HOST_SMOOTH_SCROLL_CALCULATOR_H_