Plumb smooth scrolling in Chromium compositor

ui/events/gestures/blink/web_gesture_curve_impl.h

 // 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.
 
 #ifndef UI_EVENTS_GESTURES_BLINK_WEB_GESTURE_CURVE_IMPL_H_
 #define UI_EVENTS_GESTURES_BLINK_WEB_GESTURE_CURVE_IMPL_H_
 
 #include "base/macros.h"
 #include "base/memory/scoped_ptr.h"
+#include "base/time/time.h"
 #include "third_party/WebKit/public/platform/WebGestureCurve.h"
 #include "ui/gfx/geometry/vector2d_f.h"
 
 namespace blink {
 class WebGestureCurveTarget;
 }
 
 namespace ui {
 class GestureCurve;
 
 class WebGestureCurveImpl : public NON_EXPORTED_BASE(blink::WebGestureCurve) {
  public:
   static scoped_ptr<blink::WebGestureCurve> CreateFromDefaultPlatformCurve(
       const gfx::Vector2dF& initial_velocity,
       const gfx::Vector2dF& initial_offset,
       bool on_main_thread);
+
+  static scoped_ptr<WebGestureCurve> CreateFromSmoothScrollingCurve(
+      float start_x,
+      float start_y,
+      float dx,
+      float dy,
+      base::TimeDelta duration,
+      bool on_main_thread);
+
   static scoped_ptr<blink::WebGestureCurve> CreateFromUICurveForTesting(
       scoped_ptr<GestureCurve> curve,
       const gfx::Vector2dF& initial_offset);
 
   virtual ~WebGestureCurveImpl();
 
   // WebGestureCurve implementation.
   virtual bool apply(double time,
                      blink::WebGestureCurveTarget* target) override;
 
@@ skipping 16 matching lines @@
   int64 ticks_since_first_animate_;
   double first_animate_time_;
   double last_animate_time_;
 
   DISALLOW_COPY_AND_ASSIGN(WebGestureCurveImpl);
 };
 
 }  // namespace ui
 
 #endif  // UI_EVENTS_GESTURES_BLINK_WEB_GESTURE_CURVE_IMPL_H_