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diff --git a/chromium/content/child/touch_fling_gesture_curve.cc b/chromium/content/child/touch_fling_gesture_curve.cc
new file mode 100644
index 00000000000..cc94bd62128
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+++ b/chromium/content/child/touch_fling_gesture_curve.cc
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+// Copyright 2014 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.
+
+#include "content/child/touch_fling_gesture_curve.h"
+
+#include <cmath>
+
+#include "base/debug/trace_event.h"
+#include "base/logging.h"
+#include "third_party/WebKit/public/platform/WebFloatPoint.h"
+#include "third_party/WebKit/public/platform/WebFloatSize.h"
+#include "third_party/WebKit/public/platform/WebGestureCurve.h"
+#include "third_party/WebKit/public/platform/WebGestureCurveTarget.h"
+#include "third_party/WebKit/public/platform/WebSize.h"
+
+using blink::WebFloatPoint;
+using blink::WebFloatSize;
+using blink::WebGestureCurve;
+using blink::WebGestureCurveTarget;
+using blink::WebSize;
+
+namespace {
+
+const char* kCurveName = "TouchFlingGestureCurve";
+
+inline double position(double t, float* p) {
+  return p[0] * exp(-p[2] * t) - p[1] * t - p[0];
+}
+
+inline double velocity(double t, float* p) {
+  return -p[0] * p[2] * exp(-p[2] * t) - p[1];
+}
+
+inline double timeAtVelocity(double v, float* p) {
+    DCHECK(p[0]);
+    DCHECK(p[2]);
+    return -log((v + p[1]) / (-p[0] * p[2])) / p[2];
+}
+
+} // namespace
+
+
+namespace content {
+
+// This curve implementation is based on the notion of a single, absolute
+// curve, which starts at a large velocity and smoothly decreases to
+// zero. For a given input velocity, we find where on the curve this
+// velocity occurs, and start the animation at this point---denoted by
+// (time_offset_, position_offset_).
+//
+// This has the effect of automatically determining an animation duration
+// that scales with input velocity, as faster initial velocities start
+// earlier on the curve and thus take longer to reach the end. No
+// complicated time scaling is required.
+//
+// Since the starting velocity is implicitly determined by our starting
+// point, we only store the relative magnitude and direction of both
+// initial x- and y-velocities, and use this to scale the computed
+// displacement at any point in time. This guarantees that fling
+// trajectories are straight lines when viewed in x-y space. Initial
+// velocities that lie outside the max velocity are constrained to start
+// at zero (and thus are implicitly scaled).
+//
+// The curve is modelled as a 4th order polynomial, starting at t = 0,
+// and ending at t = curve_duration_. Attempts to generate
+// position/velocity estimates outside this range are undefined.
+
+WebGestureCurve* TouchFlingGestureCurve::Create(
+    const WebFloatPoint& initial_velocity,
+    float p0,
+    float p1,
+    float p2,
+    const WebSize& cumulative_scroll) {
+  return new TouchFlingGestureCurve(initial_velocity, p0, p1, p2,
+                                    cumulative_scroll);
+}
+
+TouchFlingGestureCurve::TouchFlingGestureCurve(
+    const WebFloatPoint& initial_velocity,
+    float alpha,
+    float beta,
+    float gamma,
+    const WebSize& cumulative_scroll)
+    : cumulative_scroll_(WebFloatSize(cumulative_scroll.width,
+                                      cumulative_scroll.height)) {
+  DCHECK(initial_velocity != WebFloatPoint());
+
+  coefficients_[0] = alpha;
+  coefficients_[1] = beta;
+  coefficients_[2] = gamma;
+
+  // Curve ends when velocity reaches zero.
+  curve_duration_ = timeAtVelocity(0, coefficients_);
+  DCHECK(curve_duration_ > 0);
+
+  float max_start_velocity = std::max(fabs(initial_velocity.x),
+                                      fabs(initial_velocity.y));
+
+  // Force max_start_velocity to lie in the range v(0) to v(curve_duration),
+  // and assume that the curve parameters define a monotonically decreasing
+  // velocity, or else bisection search may fail.
+  if (max_start_velocity > velocity(0, coefficients_))
+    max_start_velocity = velocity(0, coefficients_);
+
+  if (max_start_velocity < 0)
+    max_start_velocity = 0;
+
+  // We keep track of relative magnitudes and directions of the
+  // velocity/displacement components here.
+  displacement_ratio_ = WebFloatPoint(initial_velocity.x / max_start_velocity,
+                                      initial_velocity.y / max_start_velocity);
+
+  // Compute time-offset for start velocity.
+  time_offset_ = timeAtVelocity(max_start_velocity, coefficients_);
+
+  // Compute curve position at offset time
+  position_offset_ = position(time_offset_, coefficients_);
+  TRACE_EVENT_ASYNC_BEGIN1("input", "GestureAnimation", this, "curve",
+      kCurveName);
+}
+
+TouchFlingGestureCurve::~TouchFlingGestureCurve() {
+  TRACE_EVENT_ASYNC_END0("input", "GestureAnimation", this);
+}
+
+bool TouchFlingGestureCurve::apply(double time, WebGestureCurveTarget* target) {
+  // If the fling has yet to start, simply return and report true to prevent
+  // fling termination.
+  if (time <= 0)
+    return true;
+
+  float displacement;
+  float speed;
+  if (time + time_offset_ < curve_duration_) {
+    displacement =
+        position(time + time_offset_, coefficients_) - position_offset_;
+    speed = velocity(time + time_offset_, coefficients_);
+  } else {
+    displacement = position(curve_duration_, coefficients_) - position_offset_;
+    speed = 0.f;
+  }
+
+  // Keep track of integer portion of scroll thus far, and prepare increment.
+  WebFloatSize scroll(displacement * displacement_ratio_.x,
+                      displacement * displacement_ratio_.y);
+  WebFloatSize scroll_increment(scroll.width - cumulative_scroll_.width,
+                                scroll.height - cumulative_scroll_.height);
+  WebFloatSize scroll_velocity(speed * displacement_ratio_.x,
+                               speed * displacement_ratio_.y);
+  cumulative_scroll_ = scroll;
+
+  if (time + time_offset_ < curve_duration_ ||
+      scroll_increment != WebFloatSize()) {
+    // scrollBy() could delete this curve if the animation is over, so don't
+    // touch any member variables after making that call.
+    return target->scrollBy(scroll_increment, scroll_velocity);
+  }
+
+  return false;
+}
+
+} // namespace content