Consolidate content fling implementations

content/child/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 CONTENT_CHILD_WEB_GESTURE_CURVE_IMPL_H_
+#define CONTENT_CHILD_WEB_GESTURE_CURVE_IMPL_H_
+
+#include "base/macros.h"
+#include "base/memory/scoped_ptr.h"
+#include "content/common/content_export.h"
+#include "third_party/WebKit/public/platform/WebGestureCurve.h"
+#include "ui/gfx/geometry/vector2d_f.h"
+
+namespace blink {
+class WebGestureCurveTarget;
+}
+
+namespace ui {
+class GestureCurve;
+}
+
+namespace content {
+
+class CONTENT_EXPORT WebGestureCurveImpl : public blink::WebGestureCurve {
+ public:
+  static scoped_ptr<blink::WebGestureCurve> CreateFromDefaultPlatformCurve(
+      const gfx::Vector2dF& initial_velocity,
+      const gfx::Vector2dF& initial_offset);
+  static scoped_ptr<blink::WebGestureCurve> CreateFrom(
+      scoped_ptr<ui::GestureCurve> curve,
+      const gfx::Vector2dF& initial_offset);
+
+  virtual ~WebGestureCurveImpl();
+
+  // WebGestureCurve implementation.
+  virtual bool apply(double time,
+                     blink::WebGestureCurveTarget* target) override;
+
+ private:
+  WebGestureCurveImpl(scoped_ptr<ui::GestureCurve> curve,
+                      const gfx::Vector2dF& initial_offset);
+
+  scoped_ptr<ui::GestureCurve> curve_;
+
+  gfx::Vector2dF last_offset_;
+
+  DISALLOW_COPY_AND_ASSIGN(WebGestureCurveImpl);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_CHILD_WEB_GESTURE_CURVE_IMPL_H_