[head] Add is_expanded() internally

Fixes https://github.com/harfbuzz/harfbuzz/issues/3263
diff --git a/src/hb-ot-head-table.hh b/src/hb-ot-head-table.hh
index ac588e3..20991aa 100644
--- a/src/hb-ot-head-table.hh
+++ b/src/hb-ot-head-table.hh
@@ -72,12 +72,14 @@
     UNDERLINE	= 1u<<2,
     OUTLINE	= 1u<<3,
     SHADOW	= 1u<<4,
-    CONDENSED	= 1u<<5
+    CONDENSED	= 1u<<5,
+    EXPANDED	= 1u<<6,
   };
 
   bool is_bold () const      { return macStyle & BOLD; }
   bool is_italic () const    { return macStyle & ITALIC; }
   bool is_condensed () const { return macStyle & CONDENSED; }
+  bool is_expanded () const  { return macStyle & EXPANDED; }
 
   bool sanitize (hb_sanitize_context_t *c) const
   {