function stateChangeListener() {
  console.log(this.name, 'permission status changed to', this.state);
}
function queryAndTrackPermission(permissionName) {
  navigator.permissions.query({name: permissionName}).then(function(permissionStatus) {
    console.log(permissionName, 'permission state is', permissionStatus.state);
    permissionStatus.onchange = stateChangeListener;
  });
};
queryAndTrackPermission('geolocation');
queryAndTrackPermission('midi');