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

chrome/browser/ui/libgtk2ui/select_file_dialog_impl_gtk2.cc

Index: chrome/browser/ui/libgtk2ui/select_file_dialog_impl_gtk2.cc
diff --git a/chrome/browser/ui/libgtk2ui/select_file_dialog_impl_gtk2.cc b/chrome/browser/ui/libgtk2ui/select_file_dialog_impl_gtk2.cc
index 3626255d9a851a26885e85b174d017908a9b9719..77863f1d3e1dd04cde5976ad5bd89353ac76b9fd 100644
--- a/chrome/browser/ui/libgtk2ui/select_file_dialog_impl_gtk2.cc
+++ b/chrome/browser/ui/libgtk2ui/select_file_dialog_impl_gtk2.cc
@@ -42,7 +42,7 @@ void SetGtkTransientForAura(GtkWidget* dialog, aura::Window* parent) {
   // display server ever happens. Otherwise, this will crash.
   XSetTransientForHint(GDK_WINDOW_XDISPLAY(gdk_window),
                        GDK_WINDOW_XID(gdk_window),
-                       parent->GetRootWindow()->GetAcceleratedWidget());
+                       parent->GetDispatcher()->GetAcceleratedWidget());
 
   // We also set the |parent| as a property of |dialog|, so that we can unlink
   // the two later.