[gtk+] Fix another header guard oversight

[Matthias Clasen <matthiasc src gnome org>]

commit 17fec70022c30695ca9a1cbaab4494f92668a317
Author: Matthias Clasen <mclasen redhat com>
Date:   Mon Dec 8 19:34:23 2014 -0500

    Fix another header guard oversight
    
    Pointed out in https://bugzilla.gnome.org/show_bug.cgi?id=741252

 tests/variable.h |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/tests/variable.h b/tests/variable.h
index 7246689..cc73022 100644
--- a/tests/variable.h
+++ b/tests/variable.h
@@ -1,5 +1,5 @@
 #ifndef __VARIABLE_H__
-#define __VARAIBLE_H__
+#define __VARIABLE_H__
 
 typedef struct
 {