Add commented-out dummy struct for Extension lookups.

2007-10-24  Behdad Esfahbod  <behdad@gnome.org>

        * pango/opentype/harfbuzz-gpos-private.h:
        * pango/opentype/harfbuzz-gsub-private.h:
        Add commented-out dummy struct for Extension lookups.

src/harfbuzz-gpos-private.h

@@ -655,6 +655,19 @@ struct  HB_ChainContextPos_
 typedef struct HB_ChainContextPos_  HB_ChainContextPos;
 
 
+#if 0
+/* LookupType 10 */
+struct HB_ExtensionPos_
+{
+  FT_UShort      PosFormat;           /* always 1 */
+  FT_UShort      LookuptType;         /* lookup-type of referenced subtable */
+  HB_GPOS_SubTable *subtable;         /* referenced subtable */
+};
+
+typedef struct HB_ExtensionPos_  HB_ExtensionPos;
+#endif
+
+
 union  HB_GPOS_SubTable_
 {
   HB_SinglePos        single;

src/harfbuzz-gsub-private.h

@@ -403,6 +403,19 @@ struct  HB_ChainContextSubst_
 typedef struct HB_ChainContextSubst_  HB_ChainContextSubst;
 
 
+#if 0
+/* LookupType 7 */
+struct HB_ExtensionSubst_
+{
+  FT_UShort      SubstFormat;         /* always 1 */
+  FT_UShort      LookuptType;         /* lookup-type of referenced subtable */
+  HB_GSUB_SubTable *subtable;         /* referenced subtable */
+};
+
+typedef struct HB_ExtensionSubst_  HB_ExtensionSubst;
+#endif
+
+
 /* LookupType 8 */
 struct HB_ReverseChainContextSubst_
 {