Make GetRootWindow() return a Window instead of a RootWindow.

ui/views/drag_utils.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/views/drag_utils.h"
 
 #include "ui/gfx/canvas.h"
 #include "ui/gfx/size.h"
 
 #if defined(USE_AURA)
@@ skipping 29 matching lines @@
 
 namespace views {
 
 void RunShellDrag(gfx::NativeView view,
                   const ui::OSExchangeData& data,
                   const gfx::Point& location,
                   int operation,
                   ui::DragDropTypes::DragEventSource source) {
 #if defined(USE_AURA)
   gfx::Point root_location(location);
-  aura::RootWindow* root_window = view->GetRootWindow();
+  aura::Window* root_window = view->GetRootWindow();
   aura::Window::ConvertPointToTarget(view, root_window, &root_location);
   if (aura::client::GetDragDropClient(root_window)) {
     aura::client::GetDragDropClient(root_window)->StartDragAndDrop(
         data, root_window, view, root_location, operation, source);
   }
 #elif defined(OS_WIN)
   scoped_refptr<ui::DragSourceWin> drag_source(new ui::DragSourceWin);
   DWORD effects;
   DoDragDrop(ui::OSExchangeDataProviderWin::GetIDataObject(data),
              drag_source,
              ui::DragDropTypes::DragOperationToDropEffect(operation),
              &effects);
 #endif
 }
 
 gfx::Canvas* GetCanvasForDragImage(views::Widget* widget,
                                    const gfx::Size& canvas_size) {
   float device_scale = GetDeviceScaleForNativeView(widget);
   return new gfx::Canvas(canvas_size, device_scale, false);
 }
 
 }  // namespace views