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

ui/base/dragdrop/drag_utils_win.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/base/dragdrop/drag_utils.h"
 
 #include <objidl.h>
 #include <shlobj.h>
 #include <shobjidl.h>
 
 #include "base/win/scoped_comptr.h"
 #include "third_party/skia/include/core/SkBitmap.h"
 #include "ui/base/dragdrop/os_exchange_data.h"
 #include "ui/base/dragdrop/os_exchange_data_provider_win.h"
 #include "ui/gfx/canvas.h"
 #include "ui/gfx/gdi_util.h"
 #include "ui/gfx/image/image_skia.h"
 #include "ui/gfx/skbitmap_operations.h"
 
 namespace drag_utils {
 
 static void SetDragImageOnDataObject(HBITMAP hbitmap,
                                      const gfx::Size& size,
-                                     const gfx::Point& cursor_offset,
+                                     const gfx::Vector2d& cursor_offset,
                                      IDataObject* data_object) {
   base::win::ScopedComPtr<IDragSourceHelper> helper;
   HRESULT rv = CoCreateInstance(CLSID_DragDropHelper, 0, CLSCTX_INPROC_SERVER,
                                 IID_IDragSourceHelper, helper.ReceiveVoid());
   if (SUCCEEDED(rv)) {
     SHDRAGIMAGE sdi;
     sdi.sizeDragImage = size.ToSIZE();
     sdi.crColorKey = 0xFFFFFFFF;
     sdi.hbmpDragImage = hbitmap;
-    sdi.ptOffset = cursor_offset.ToPOINT();
+    sdi.ptOffset = gfx::PointAtOffsetFromOrigin(cursor_offset).ToPOINT();
     helper->InitializeFromBitmap(&sdi, data_object);
   }
 }
 
 // Blit the contents of the canvas to a new HBITMAP. It is the caller's
 // responsibility to release the |bits| buffer.
 static HBITMAP CreateHBITMAPFromSkBitmap(const SkBitmap& sk_bitmap) {
   HDC screen_dc = GetDC(NULL);
   BITMAPINFOHEADER header;
   gfx::CreateBitmapHeader(sk_bitmap.width(), sk_bitmap.height(), &header);
   void* bits;
   HBITMAP bitmap =
       CreateDIBSection(screen_dc, reinterpret_cast<BITMAPINFO*>(&header),
                        DIB_RGB_COLORS, &bits, NULL, 0);
   DCHECK(sk_bitmap.rowBytes() == sk_bitmap.width() * 4);
   SkAutoLockPixels lock(sk_bitmap);
   memcpy(
       bits, sk_bitmap.getPixels(), sk_bitmap.height() * sk_bitmap.rowBytes());
   ReleaseDC(NULL, screen_dc);
   return bitmap;
 }
 
 void SetDragImageOnDataObject(const gfx::ImageSkia& image_skia,
                               const gfx::Size& size,
-                              const gfx::Point& cursor_offset,
+                              const gfx::Vector2d& cursor_offset,
                               ui::OSExchangeData* data_object) {
   DCHECK(data_object && !size.IsEmpty());
   // InitializeFromBitmap() doesn't expect an alpha channel and is confused
   // by premultiplied colors, so unpremultiply the bitmap.
   // SetDragImageOnDataObject(HBITMAP) takes ownership of the bitmap.
   HBITMAP bitmap = CreateHBITMAPFromSkBitmap(
       SkBitmapOperations::UnPreMultiply(*image_skia.bitmap()));
 
   // Attach 'bitmap' to the data_object.
   SetDragImageOnDataObject(bitmap, size, cursor_offset,
       ui::OSExchangeDataProviderWin::GetIDataObject(*data_object));
 }
 
 }  // namespace drag_utils