message: gltfpack: Minor cleanup
  Checking data::bin is more direct and cleaner. Also we can use `s`
  directly instead of streams.back.
diff: @@ -196,7 +196,7 @@ static void parseMeshesGltf(cgltf_data* data, std::vector<Mesh>& meshes)
  if (attr.type == cgltf_attribute_type_color && attr.data->type == cgltf_type_vec3)
  {
  - for (size_t i = 0; i < result.streams.back().data.size(); ++i)
  + for (size_t i = 0; i < s.data.size(); ++i)
  s.data[i].f[3] = 1.0f;
  }
  }
  @@ -462,12 +462,9 @@ cgltf_data* parseGltf(const char* path, std::vector<Mesh>& meshes, std::vector<A
  {
  evacuateExtras(data, extras);
  - if (data->json == data->file_data)
  - {
  - assert(!data->bin);
  + if (!data->bin)
  freeFile(data);
  }
  - }
  result = (result == cgltf_result_success) ? cgltf_load_buffers(&options, data, path) : result;
  result = (result == cgltf_result_success) ? cgltf_validate(data) : result;
  @@ -495,11 +492,8 @@ cgltf_data* parseGltf(const char* path, std::vector<Mesh>& meshes, std::vector<A
  bool free_bin = freeUnusedBuffers(data);
  - if (free_bin)
  - {
  - assert(data->bin);
  + if (data->bin && free_bin)
  freeFile(data);
  - }
  return data;
  }
  