Make aura::clients take Window instead of RootWindow

ui/views/widget/desktop_aura/desktop_drag_drop_client_win.h

Index: ui/views/widget/desktop_aura/desktop_drag_drop_client_win.h
diff --git a/ui/views/widget/desktop_aura/desktop_drag_drop_client_win.h b/ui/views/widget/desktop_aura/desktop_drag_drop_client_win.h
index 7aa4952ab39a7ae5cb50fb7306a2a8c2776e824b..042a5a8a3c3b10b269915416caed9d3c7e05443c 100644
--- a/ui/views/widget/desktop_aura/desktop_drag_drop_client_win.h
+++ b/ui/views/widget/desktop_aura/desktop_drag_drop_client_win.h
@@ -12,7 +12,6 @@
 
 namespace ui {
 class DragSourceWin;
-class RootWindow;
 }
 
 namespace views {
@@ -22,13 +21,13 @@ class DesktopDropTargetWin;
 class VIEWS_EXPORT DesktopDragDropClientWin
     : public aura::client::DragDropClient {
  public:
-  DesktopDragDropClientWin(aura::RootWindow* root_window, HWND window);
+  DesktopDragDropClientWin(aura::Window* root_window, HWND window);
   virtual ~DesktopDragDropClientWin();
 
   // Overridden from aura::client::DragDropClient:
   virtual int StartDragAndDrop(
       const ui::OSExchangeData& data,
-      aura::RootWindow* root_window,
+      aura::Window* root_window,
       aura::Window* source_window,
       const gfx::Point& root_location,
       int operation,