[subset-plan] Simplify colrv1_layers allocation

src/OT/Color/COLR/COLR.hh

@@ -550,7 +550,7 @@ struct PaintColrLayers
     TRACE_SUBSET (this);
     auto *out = c->serializer->embed (this);
     if (unlikely (!out)) return_trace (false);
-    return_trace (c->serializer->check_assign (out->firstLayerIndex, c->plan->colrv1_layers->get (firstLayerIndex),
+    return_trace (c->serializer->check_assign (out->firstLayerIndex, c->plan->colrv1_layers.get (firstLayerIndex),
                                                HB_SERIALIZE_ERROR_INT_OVERFLOW));
 
     return_trace (true);

src/hb-subset-plan.cc

@@ -657,7 +657,7 @@ _populate_gids_to_retain (hb_subset_plan_t* plan,
   hb_set_t cur_glyphset = plan->_glyphset_mathed;
   if (!drop_tables->has (HB_OT_TAG_COLR))
   {
-    _colr_closure (plan->source, plan->colrv1_layers, plan->colr_palettes, &cur_glyphset);
+    _colr_closure (plan->source, &plan->colrv1_layers, plan->colr_palettes, &cur_glyphset);
     _remove_invalid_gids (&cur_glyphset, plan->source->get_num_glyphs ());
   }
 
@@ -857,7 +857,6 @@ hb_subset_plan_create_or_fail (hb_face_t	 *face,
   plan->reverse_glyph_map = hb_map_create ();
   plan->glyph_map_gsub = hb_map_create ();
 
-  plan->colrv1_layers = hb_map_create ();
   plan->colr_palettes = hb_map_create ();
   plan->check_success (plan->layout_variation_idx_delta_map = hb_hashmap_create<unsigned, hb_pair_t<unsigned, int>> ());
   plan->gdef_varstore_inner_maps.init ();

src/hb-subset-plan.hh

@@ -58,7 +58,6 @@ struct hb_subset_plan_t
     hb_map_destroy (glyph_map);
     hb_map_destroy (reverse_glyph_map);
     hb_map_destroy (glyph_map_gsub);
-    hb_map_destroy (colrv1_layers);
     hb_map_destroy (colr_palettes);
     hb_map_destroy (axes_index_map);
     hb_map_destroy (axes_old_index_tag_map);
@@ -159,7 +158,7 @@ struct hb_subset_plan_t
   hb_hashmap_t<unsigned, const OT::Feature*> gpos_feature_substitutes_map;
 
   //active layers/palettes we'd like to retain
-  hb_map_t *colrv1_layers;
+  hb_map_t colrv1_layers;
   hb_map_t *colr_palettes;
 
   //Old layout item variation index -> (New varidx, delta) mapping