Roll harfbuzz-ng to 1.0.5

third_party/harfbuzz-ng/src/hb-shape-plan.cc

Index: third_party/harfbuzz-ng/src/hb-shape-plan.cc
diff --git a/third_party/harfbuzz-ng/src/hb-shape-plan.cc b/third_party/harfbuzz-ng/src/hb-shape-plan.cc
index d2f293d69dedc5a3a34239b0166e2fb15bd57345..56e2ea5c19254c1f94e696efba5b01151446ec66 100644
--- a/third_party/harfbuzz-ng/src/hb-shape-plan.cc
+++ b/third_party/harfbuzz-ng/src/hb-shape-plan.cc
@@ -128,7 +128,7 @@ hb_shape_plan_create (hb_face_t                     *face,
     face = hb_face_get_empty ();
   if (unlikely (!props))
     return hb_shape_plan_get_empty ();
-  if (num_user_features && !(features = (hb_feature_t *) malloc (num_user_features * sizeof (hb_feature_t))))
+  if (num_user_features && !(features = (hb_feature_t *) calloc (num_user_features, sizeof (hb_feature_t))))
     return hb_shape_plan_get_empty ();
   if (!(shape_plan = hb_object_create<hb_shape_plan_t> ())) {
     free (features);
@@ -293,8 +293,13 @@ hb_shape_plan_execute (hb_shape_plan_t    *shape_plan,
 		  num_features,
 		  shape_plan->shaper_func);
 
-  if (unlikely (hb_object_is_inert (shape_plan) ||
-		hb_object_is_inert (buffer)))
+  if (unlikely (!buffer->len))
+    return true;
+
+  assert (!hb_object_is_inert (buffer));
+  assert (buffer->content_type == HB_BUFFER_CONTENT_TYPE_UNICODE);
+
+  if (unlikely (hb_object_is_inert (shape_plan)))
     return false;
 
   assert (shape_plan->face_unsafe == font->face);