[gtk+] gdkdisplay-x11: Don't do extra work when simply moving the window

[Jasper St. Pierre <jstpierre src gnome org>]

commit fe8f6f60dcb70178b68315dab232a6cfe7aa0b0e
Author: Jasper St. Pierre <jstpierre mecheye net>
Date:   Wed Nov 26 17:07:56 2014 -0800

    gdkdisplay-x11: Don't do extra work when simply moving the window
    
    We shouldn't bother recalculating all the visible regions and wiping
    away the old updating areas if we're simply dragging the window around.

 gdk/x11/gdkdisplay-x11.c |   17 +++++++++++------
 1 files changed, 11 insertions(+), 6 deletions(-)
---
diff --git a/gdk/x11/gdkdisplay-x11.c b/gdk/x11/gdkdisplay-x11.c
index d6543c1..89c2b7d 100644
--- a/gdk/x11/gdkdisplay-x11.c
+++ b/gdk/x11/gdkdisplay-x11.c
@@ -828,13 +828,18 @@ gdk_x11_display_translate_event (GdkEventTranslator *translator,
            {
              window->x = event->configure.x;
              window->y = event->configure.y;
-              window_impl->unscaled_width = xevent->xconfigure.width;
-              window_impl->unscaled_height = xevent->xconfigure.height;
-              window->width = event->configure.width;
-              window->height = event->configure.height;
 
-             _gdk_window_update_size (window);
-             _gdk_x11_window_update_size (window_impl);
+              if (window_impl->unscaled_width != xevent->xconfigure.width ||
+                  window_impl->unscaled_height != xevent->xconfigure.height)
+                {
+                  window_impl->unscaled_width = xevent->xconfigure.width;
+                  window_impl->unscaled_height = xevent->xconfigure.height;
+                  window->width = event->configure.width;
+                  window->height = event->configure.height;
+
+                  _gdk_window_update_size (window);
+                  _gdk_x11_window_update_size (window_impl);
+                }
 
              if (window->resize_count >= 1)
                {