[mutter] iconcache: Fix a dumb thinko

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

commit 7966f00a18bb17c370a26e777178fc2ceb933bcb
Author: Jasper St. Pierre <jstpierre mecheye net>
Date:   Tue Feb 17 23:33:44 2015 -0800

    iconcache: Fix a dumb thinko
    
    This is an xlib surface, not an image surface.

 src/x11/iconcache.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/src/x11/iconcache.c b/src/x11/iconcache.c
index b205ab6..71b7417 100644
--- a/src/x11/iconcache.c
+++ b/src/x11/iconcache.c
@@ -349,8 +349,8 @@ try_pixmap_and_mask (MetaDisplay      *display,
 
       masked = cairo_surface_create_similar_image (icon,
                                                    CAIRO_FORMAT_ARGB32,
-                                                   cairo_image_surface_get_width (icon),
-                                                   cairo_image_surface_get_height (icon));
+                                                   cairo_xlib_surface_get_width (icon),
+                                                   cairo_xlib_surface_get_height (icon));
       cr = cairo_create (masked);
 
       cairo_set_source_surface (cr, icon, 0, 0);