backoffice/node_modules/core-js/library/modules/es6.object.keys.js

// 19.1.2.14 Object.keys(O)
var toObject = require('./_to-object')
  , $keys    = require('./_object-keys');

require('./_object-sap')('keys', function(){
  return function keys(it){
    return $keys(toObject(it));
  };
});