Refactor
diff --git a/src/hb-ot-layout-gsubgpos-private.hh b/src/hb-ot-layout-gsubgpos-private.hh
index baf0cb3..da31bdf 100644
--- a/src/hb-ot-layout-gsubgpos-private.hh
+++ b/src/hb-ot-layout-gsubgpos-private.hh
@@ -79,20 +79,16 @@
   const hb_codepoint_t *glyphs;
   unsigned int len;
   bool zero_context;
-  const hb_set_digest_t digest;
   unsigned int debug_depth;
 
   hb_would_apply_context_t (hb_face_t *face_,
 			    const hb_codepoint_t *glyphs_,
 			    unsigned int len_,
-			    bool zero_context_,
-			    const hb_set_digest_t &digest_
-			    ) :
+			    bool zero_context_) :
 			      face (face_),
 			      glyphs (glyphs_),
 			      len (len_),
 			      zero_context (zero_context_),
-			      digest (digest_),
 			      debug_depth (0) {};
 };
 
@@ -118,21 +114,18 @@
   unsigned int debug_depth;
   const GDEF &gdef;
   bool has_glyph_classes;
-  const hb_set_digest_t digest;
 
 
   hb_apply_context_t (hb_font_t *font_,
 		      hb_buffer_t *buffer_,
-		      hb_mask_t lookup_mask_,
-		      const hb_set_digest_t &digest_) :
+		      hb_mask_t lookup_mask_) :
 			font (font_), face (font->face), buffer (buffer_),
 			direction (buffer_->props.direction),
 			lookup_mask (lookup_mask_),
 			nesting_level_left (MAX_NESTING_LEVEL),
 			lookup_props (0), property (0), debug_depth (0),
 			gdef (*hb_ot_layout_from_face (face)->gdef),
-			has_glyph_classes (gdef.has_glyph_classes ()),
-			digest (digest_) {}
+			has_glyph_classes (gdef.has_glyph_classes ()) {}
 
   void set_lookup_props (unsigned int lookup_props_) {
     lookup_props = lookup_props_;