ui: Prefer +/- operators to apply offsets.

ui/gfx/point_f.h

 // 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.
 
 #ifndef UI_GFX_POINT_F_H_
 #define UI_GFX_POINT_F_H_
 
 #include <string>
 
 #include "ui/base/ui_export.h"
@@ skipping 35 matching lines @@
   return result;
 }
 
 inline PointF operator-(const PointF& lhs, const Vector2dF& rhs) {
   PointF result(lhs);
   result -= rhs;
   return result;
 }
 
 inline Vector2dF operator-(const PointF& lhs, const PointF& rhs) {
-  return lhs.OffsetFrom(rhs);
+  return Vector2dF(lhs.x() - rhs.x(), lhs.y() - rhs.y());
 }
 
 inline PointF PointAtOffsetFromOrigin(const Vector2dF& offset_from_origin) {
   return PointF(offset_from_origin.x(), offset_from_origin.y());
 }
 
 UI_EXPORT PointF ScalePoint(const PointF& p, float x_scale, float y_scale);
 
 inline PointF ScalePoint(const PointF& p, float scale) {
   return ScalePoint(p, scale, scale);
 }
 
 #if !defined(COMPILER_MSVC)
 extern template class PointBase<PointF, float, Vector2dF>;
 #endif
 
 }  // namespace gfx
 
 #endif  // UI_GFX_POINT_F_H_