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

ui/views/widget/x11_desktop_window_move_client.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_VIEWS_WIDGET_X11_DESKTOP_WINDOW_MOVE_CLIENT_H_
 #define UI_VIEWS_WIDGET_X11_DESKTOP_WINDOW_MOVE_CLIENT_H_
 
 #include "base/callback.h"
 #include "base/compiler_specific.h"
 #include "ui/aura/client/window_move_client.h"
@@ skipping 18 matching lines @@
                                    ui::MouseEvent* event) OVERRIDE;
   virtual ui::TouchStatus PreHandleTouchEvent(aura::Window* target,
                                               ui::TouchEvent* event) OVERRIDE;
   virtual ui::EventResult PreHandleGestureEvent(
       aura::Window* target,
       ui::GestureEvent* event) OVERRIDE;
 
   // Overridden from aura::client::WindowMoveClient:
   virtual aura::client::WindowMoveResult RunMoveLoop(
       aura::Window* window,
-      const gfx::Point& drag_offset) OVERRIDE;
+      const gfx::Vector2d& drag_offset) OVERRIDE;
   virtual void EndMoveLoop() OVERRIDE;
 
  private:
   // Are we running a nested message loop from RunMoveLoop()?
   bool in_move_loop_;
 
   // Our cursor offset from the top left window origin when the drag
   // started. Used to calculate the window's new bounds relative to the current
   // location of the cursor.
-  gfx::Point window_offset_;
+  gfx::Vector2d window_offset_;
 
   base::Closure quit_closure_;
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_WIDGET_X11_DESKTOP_WINDOW_MOVE_CLIENT_H_