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

ash/drag_drop/drag_drop_controller.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 ASH_DRAG_DROP_DRAG_DROP_CONTROLLER_H_
 #define ASH_DRAG_DROP_DRAG_DROP_CONTROLLER_H_
 
 #include "ash/ash_export.h"
 #include "base/callback.h"
 #include "ui/aura/client/drag_drop_client.h"
@@ skipping 70 matching lines @@
   // Implementation of ImplicitAnimationObserver
   virtual void OnImplicitAnimationsCompleted() OVERRIDE;
 
   // Helper method to start drag widget flying back animation.
   void StartCanceledAnimation();
 
   // Helper method to reset everything.
   void Cleanup();
 
   scoped_ptr<DragImageView> drag_image_;
-  gfx::Point drag_image_offset_;
+  gfx::Vector2d drag_image_offset_;
   const ui::OSExchangeData* drag_data_;
   int drag_operation_;
 
   // Window that is currently under the drag cursor.
   aura::Window* drag_window_;
   gfx::Point drag_start_location_;
 
   // Indicates whether the caller should be blocked on a drag/drop session.
   // Only be used for tests.
   bool should_block_during_drag_drop_;
 
   // Closure for quitting nested message loop.
   base::Closure quit_closure_;
 
   scoped_ptr<ash::internal::DragDropTracker> drag_drop_tracker_;
 
   DISALLOW_COPY_AND_ASSIGN(DragDropController);
 };
 
 }  // namespace internal
 }  // namespace ash
 
 #endif  // ASH_DRAG_DROP_DRAG_DROP_CONTROLLER_H_