[gtk+] Revert "wayland: Push NULL buffer when hiding a GdkWindow"

[Carlos Garnacho <carlosg src gnome org>]

commit f686dfb575e1279721d11aaab1a98a9335f0dced
Author: Carlos Garnacho <carlosg gnome org>
Date:   Fri Jan 20 14:04:29 2017 +0100

    Revert "wayland: Push NULL buffer when hiding a GdkWindow"
    
    This reverts commit 6beb0b91c91dd4a018b0fe2c39f5687a00938821.

 gdk/wayland/gdkwindow-wayland.c |   11 ++++-------
 1 files changed, 4 insertions(+), 7 deletions(-)
---
diff --git a/gdk/wayland/gdkwindow-wayland.c b/gdk/wayland/gdkwindow-wayland.c
index ef7d61a..674dac5 100644
--- a/gdk/wayland/gdkwindow-wayland.c
+++ b/gdk/wayland/gdkwindow-wayland.c
@@ -2439,7 +2439,7 @@ unmap_popups_for_window (GdkWindow *window)
 }
 
 static void
-gdk_wayland_window_clear_surface (GdkWindow *window)
+gdk_wayland_window_hide_surface (GdkWindow *window)
 {
   GdkWaylandDisplay *display_wayland = GDK_WAYLAND_DISPLAY (gdk_window_get_display (window));
   GdkWindowImplWayland *impl = GDK_WINDOW_IMPL_WAYLAND (window->impl);
@@ -2534,10 +2534,7 @@ gdk_wayland_window_clear_surface (GdkWindow *window)
 static void
 gdk_wayland_window_hide (GdkWindow *window)
 {
-  GdkWindowImplWayland *impl = GDK_WINDOW_IMPL_WAYLAND (window->impl);
-
-  wl_surface_attach (impl->display_server.wl_surface, NULL, 0, 0);
-  wl_surface_commit (impl->display_server.wl_surface);
+  gdk_wayland_window_hide_surface (window);
   _gdk_window_clear_update_area (window);
 }
 
@@ -2551,7 +2548,7 @@ gdk_window_wayland_withdraw (GdkWindow *window)
 
       g_assert (!GDK_WINDOW_IS_MAPPED (window));
 
-      gdk_wayland_window_clear_surface (window);
+      gdk_wayland_window_hide_surface (window);
     }
 }
 
@@ -2838,7 +2835,7 @@ gdk_wayland_window_destroy (GdkWindow *window,
    */
   g_return_if_fail (!foreign_destroy);
 
-  gdk_wayland_window_clear_surface (window);
+  gdk_wayland_window_hide_surface (window);
   drop_cairo_surfaces (window);
 }