Let hb_face_get_table() return NULL if table not found

src/hb-font.cc

@@ -364,7 +364,7 @@ hb_face_get_table (hb_face_t *face,
 
   blob = face->get_table (tag, face->user_data);
 
-  return likely (blob) ? blob : &_hb_blob_nil;
+  return blob;
 }
 
 

src/hb-font.h

@@ -60,6 +60,7 @@ hb_face_get_reference_count (hb_face_t *face);
 void
 hb_face_destroy (hb_face_t *face);
 
+/* Returns NULL if not found */
 hb_blob_t *
 hb_face_get_table (hb_face_t *face,
 		   hb_tag_t   tag);

src/hb-open-type-private.hh

@@ -283,6 +283,9 @@ struct Sanitizer
 
     /* TODO is_sane() stuff */
 
+    if (!blob)
+      return hb_blob_create_empty ();
+
   retry:
     if (HB_DEBUG_SANITIZE)
       fprintf (stderr, "Sanitizer %p start %s\n", blob, HB_FUNC);