[pango] Use finer HarfBuzz cluster level

[Khaled Hosny <khaledh src gnome org>]

commit 3ea523f9da45c68eeab29d2d98f6a1972d0f2682
Author: Khaled Hosny <khaledhosny eglug org>
Date:   Tue Aug 18 16:21:26 2015 +0200

    Use finer HarfBuzz cluster level
    
    So that we can set attributes (e.g. colors) to the marks and their bases
    indecently.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=541608

 pango/pangofc-shape.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)
---
diff --git a/pango/pangofc-shape.c b/pango/pangofc-shape.c
index 51404f0..c9c0861 100644
--- a/pango/pangofc-shape.c
+++ b/pango/pangofc-shape.c
@@ -342,6 +342,9 @@ _pango_fc_shape (PangoFont           *font,
   hb_buffer_set_direction (hb_buffer, hb_direction);
   hb_buffer_set_script (hb_buffer, hb_glib_script_to_script (analysis->script));
   hb_buffer_set_language (hb_buffer, hb_language_from_string (pango_language_to_string (analysis->language), 
-1));
+#if HB_VERSION_ATLEAST(1,0,2)
+  hb_buffer_set_cluster_level (hb_buffer, HB_BUFFER_CLUSTER_LEVEL_MONOTONE_CHARACTERS);
+#endif
   hb_buffer_set_flags (hb_buffer,
                       (item_offset == 0 ? HB_BUFFER_FLAG_BOT : 0) |
                       (item_offset + item_length == paragraph_length ? HB_BUFFER_FLAG_EOT : 0));