Sets X11WholeScreenMoveLoop as OverrideDispatcher to get events even before grab is granted

ui/views/widget/desktop_aura/x11_whole_screen_move_loop.h

Index: ui/views/widget/desktop_aura/x11_whole_screen_move_loop.h
diff --git a/ui/views/widget/desktop_aura/x11_whole_screen_move_loop.h b/ui/views/widget/desktop_aura/x11_whole_screen_move_loop.h
index cc5fcbf551f3f3b69eccf4dac84cdae1a794d01b..34f2783a73fb34c0b661952945e0cb54e0d481bf 100644
--- a/ui/views/widget/desktop_aura/x11_whole_screen_move_loop.h
+++ b/ui/views/widget/desktop_aura/x11_whole_screen_move_loop.h
@@ -20,6 +20,10 @@ namespace aura {
 class Window;
 }
 
+namespace ui {
+class ScopedEventDispatcher;
+}
+
 namespace views {
 
 class Widget;
@@ -72,6 +76,7 @@ class X11WholeScreenMoveLoop : public ui::PlatformEventDispatcher {
 
   // Are we running a nested message loop from RunMoveLoop()?
   bool in_move_loop_;
+  scoped_ptr<ui::ScopedEventDispatcher> nested_dispatcher_;
 
   bool should_reset_mouse_flags_;