grant method
Grant a permission to the runtime.
Implementation
void grant(Permission permission) {
  for (final domain in permission.domains) {
    _permissions.putIfAbsent(domain, () => []).add(permission);
  }
}Grant a permission to the runtime.
void grant(Permission permission) {
  for (final domain in permission.domains) {
    _permissions.putIfAbsent(domain, () => []).add(permission);
  }
}