[perl-Gtk2] Fix a test failure in t/GdkWindow.t

[Torsten Schönfeld <tsch src gnome org>]

commit a81b70d65885123f9cdbbe78f06daec25897e62a
Author: Torsten Schönfeld <kaffeetisch gmx de>
Date:   Fri Aug 14 23:37:46 2015 +0200

    Fix a test failure in t/GdkWindow.t
    
    It occurs only on gtk+ >= 2.24.26 and < 2.24.29.

 t/GdkWindow.t |   14 ++++++++++++--
 1 files changed, 12 insertions(+), 2 deletions(-)
---
diff --git a/t/GdkWindow.t b/t/GdkWindow.t
index e65931b..0bfca32 100644
--- a/t/GdkWindow.t
+++ b/t/GdkWindow.t
@@ -191,9 +191,19 @@ $window -> shape_combine_region($region, 1, 1);
 $window -> shape_combine_mask(undef, 0, 0);
 $window -> shape_combine_region(undef, 0, 0);
 
+SKIP: {
+  skip 'child shapes functions trigger a bug', 0
+    if (Gtk2->CHECK_VERSION (2, 24, 26) && !Gtk2->CHECK_VERSION (2, 24, 29));
+
+  # Introduced in
+  # <https://git.gnome.org/browse/gtk+/commit/?h=gtk-2-24&id=aff976ef0dad471edc35d65b9d1b5ba97da1698e>,
+  # fixed in
+  # <https://git.gnome.org/browse/gtk+/commit/?h=gtk-2-24&id=7ee8b1fd9af52842e87c26465b9aa8921e62ec90>.
+
+  $window -> set_child_shapes();
+  $window -> merge_child_shapes();
+}
 
-$window -> set_child_shapes();
-$window -> merge_child_shapes();
 $window -> set_static_gravities(0); # FIXME: check retval?
 $window -> set_title("Blub");
 $window -> set_background(Gtk2::Gdk::Color -> new(255, 255, 255));