window: Reinstate logic for should_use_csd()

The old should_use_csd() function would return FALSE if the GTK_CSD
environment variable is unset; the change in commit c5e5ee67490e7e7
made it return TRUE if GTK_CSD is unset. This has a cascade effect
on the window size, which causes invalid rectangles to bubble down
to Pixman.

https://bugzilla.gnome.org/show_bug.cgi?id=751140

diff --git a/gtk/gtkwindow.c b/gtk/gtkwindow.c
index fb8e0b019de1984bb25355c0fddb79dde1a0dbf4..7f4e74b37f42a55eb2db3ad722953cc7e37d7d91 100644 (file)
--- a/gtk/gtkwindow.c
+++ b/gtk/gtkwindow.c
@@ -4079,8 +4079,7 @@ gtk_window_can_use_csd (GtkWindow *window)
 
   csd_env = g_getenv ("GTK_CSD");
 
-  /* If GTK_CSD is unset we default to CSD support */
-  return csd_env == NULL || (strcmp (csd_env, "1") == 0);
+  return (g_strcmp0 (csd_env, "1") == 0);
 }
 
 static void