Add Vector2d classes that represent offsets, instead of using Point.

ui/gfx/vector2d_conversions.cc

+// Copyright (c) 2012 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 "ui/gfx/vector2d_conversions.h"
+
+#include "ui/gfx/safe_integer_conversions.h"
+
+namespace gfx {
+
+Vector2d ToFlooredVector2d(const Vector2dF& vector2d) {
+  int x = ToFlooredInt(vector2d.x());
+  int y = ToFlooredInt(vector2d.y());
+  return Vector2d(x, y);
+}
+
+Vector2d ToCeiledVector2d(const Vector2dF& vector2d) {
+  int x = ToCeiledInt(vector2d.x());
+  int y = ToCeiledInt(vector2d.y());
+  return Vector2d(x, y);
+}
+
+Vector2d ToRoundedVector2d(const Vector2dF& vector2d) {
+  int x = ToRoundedInt(vector2d.x());
+  int y = ToRoundedInt(vector2d.y());
+  return Vector2d(x, y);
+}
+
+}  // namespace gfx
+