[HarfBuzz] 'dlig' in Arabic

[Jonathan Kew]

It seems that (despite what the shaping spec implies) uniscribe does not 
apply 'dlig' by default in Arabic. I think we should do the same in 
harfbuzz - i.e., apply rlig and liga, but leave dlig for the user to 
explicitly request.

JK
-------------- next part --------------
commit 85ff25c9aafdc74993a3da018ffd86d0f1f05376
Author: Jonathan Kew <jfkthame at gmail.com>
Date:   Thu Aug 1 17:09:14 2013 +0100

    [Arabic] Don't apply 'dlig' by default, despite what the Arabic shaping spec implies.

diff --git a/src/hb-ot-shape-complex-arabic.cc b/src/hb-ot-shape-complex-arabic.cc
index 7f8778a..a57e81a 100644
--- a/src/hb-ot-shape-complex-arabic.cc
+++ b/src/hb-ot-shape-complex-arabic.cc
@@ -193,7 +193,6 @@ collect_features_arabic (hb_ot_shape_planner_t *plan)
   map->add_gsub_pause (NULL);
 
   map->add_global_bool_feature (HB_TAG('c','s','w','h'));
-  map->add_global_bool_feature (HB_TAG('d','l','i','g'));
   map->add_global_bool_feature (HB_TAG('m','s','e','t'));
 }