Update tests/input.html to include keysym.js instead of keysymdef.js

tests/input.html

@@ -26,6 +26,7 @@
     <script src="../include/util.js"></script>
     <script src="../include/webutil.js"></script> 
     <script src="../include/base64.js"></script>
+    <script src="../include/keysym.js"></script>
     <script src="../include/keysymdef.js"></script> 
     <script src="../include/keyboard.js"></script> 
     <script src="../include/input.js"></script>