ui/gfx: Make gfx::Canvas inherit from gfx::CanvasSkia.

ui/views/drag_utils.cc

-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// 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/views/drag_utils.h"
 
 #include "base/file_util.h"
 #include "base/logging.h"
 #include "base/utf_string_conversions.h"
 #include "googleurl/src/gurl.h"
 #include "grit/ui_resources.h"
@@ skipping 75 matching lines @@
 
   SetDragImageOnDataObject(canvas, gfx::Size(width, height),
                            gfx::Point(width / 2, kLinkDragImageVPadding),
                            data_object);
 }
 
 void SetDragImageOnDataObject(const gfx::Canvas& canvas,
                               const gfx::Size& size,
                               const gfx::Point& cursor_offset,
                               ui::OSExchangeData* data_object) {
-  SetDragImageOnDataObject(
-      canvas.AsCanvasSkia()->ExtractBitmap(), size, cursor_offset, data_object);
+  SetDragImageOnDataObject(canvas.ExtractBitmap(), size, cursor_offset,
+                           data_object);
 }
 
 }  // namespace drag_utils