Move fling implementation from renderer to browser:

content/browser/renderer_host/input/fling/fling_curve_impl.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_INPUT_FLING_FLING_CURVE_IMPL_H_
+#define CONTENT_BROWSER_RENDERER_HOST_INPUT_FLING_FLING_CURVE_IMPL_H_
+
+#include "base/basictypes.h"
+#include "content/browser/renderer_host/input/fling/fling_curve.h"
+#include "content/common/content_export.h"
+#include "ui/gfx/point.h"
+#include "ui/gfx/point_f.h"
+
+namespace content {
+
+// Implementation of FlingCurve suitable for touch pad/screen-based
+// fling scroll. Starts with a flat velocity profile based on 'velocity', which
+// tails off to zero. Time is scaled to that duration of the fling is
+// proportional to the initial velocity.
+class FlingCurveImpl : public FlingCurve {
+ public:
+
+  CONTENT_EXPORT static FlingCurve* Create(
+      const gfx::PointF& initial_velocity,
+      float p0,
+      float p1,
+      float p2,
+      const gfx::Point& cumulative_scroll);
+
+  // Overridden from FlingCurve.
+  virtual bool Apply(double time_in_secs, FlingCurveTarget* target) OVERRIDE;
+
+ private:
+  FlingCurveImpl(const gfx::PointF& initial_velocity,
+                 float p0,
+                 float p1,
+                 float p2,
+                 const gfx::Point& cumulative_scroll);
+  virtual ~FlingCurveImpl();
+
+  gfx::PointF displacement_ratio_;
+  gfx::PointF cumulative_scroll_;
+  float coefficients_[3];
+  float time_offset_;
+  float curve_duration_;
+  float position_offset_;
+
+  DISALLOW_COPY_AND_ASSIGN(FlingCurveImpl);
+};
+
+} // namespace content
+
+#endif // CONTENT_BROWSER_RENDERER_HOST_INPUT_FLING_FLING_CURVE_IMPL_H_