code: function hasChanged(depValues, current, dependencies) {
    var len = dependencies.length;
    var i = 0;
    var result = false;
    while (len--) {
      var dep = dependencies[i++];
      var value = get(current, dep);
      if (get(depValues, dep) !== value) {
        result = true;
        set(depValues, dep, value);
      }
    }
    return result;
  }
docs: Determine if dependencies have changed.
  
  @param  {Object}  `depValues` Stored dependency values
  @param  {Object}  `current` Current object to check the dependencies.
  @param  {Array}   `dependencies` Dependencies to check.
  @return {Boolean} Did any dependencies change?
  @api private