How to use the terriajs-cesium/Source/ThirdParty/knockout.default function in terriajs-cesium

var DragPoints = require("../Map/DragPoints");

var DeveloperError = require("terriajs-cesium/Source/Core/DeveloperError")
  .default;
var defined = require("terriajs-cesium/Source/Core/defined").default;
var defaultValue = require("terriajs-cesium/Source/Core/defaultValue").default;
var Color = require("terriajs-cesium/Source/Core/Color").default;
var PolylineGlowMaterialProperty = require("terriajs-cesium/Source/DataSources/PolylineGlowMaterialProperty")
  .default;
var CustomDataSource = require("terriajs-cesium/Source/DataSources/CustomDataSource")
  .default;
var CallbackProperty = require("terriajs-cesium/Source/DataSources/CallbackProperty")
  .default;
var PolygonHierarchy = require("terriajs-cesium/Source/Core/PolygonHierarchy")
  .default;
var knockout = require("terriajs-cesium/Source/ThirdParty/knockout").default;
var Entity = require("terriajs-cesium/Source/DataSources/Entity.js").default;
var when = require("terriajs-cesium/Source/ThirdParty/when").default;
var Cartesian3 = require("terriajs-cesium/Source/Core/Cartesian3").default;

/**
 * Callback for when a point is clicked.
 * @callback PointClickedCallback
 * @param {CustomDataSource} customDataSource Contains all point entities that user has selected so far
 */

/**
 * Callback for when a point is moved.
 * @callback PointMovedCallback
 * @param {CustomDataSource} customDataSource Contains all point entities that user has selected so far
 */

"use strict";

/*global require*/
var URI = require("urijs");
var defined = require("terriajs-cesium/Source/Core/defined").default;
var UrlTemplateImageryProvider = require("terriajs-cesium/Source/Scene/UrlTemplateImageryProvider")
  .default;
var defineProperties = require("terriajs-cesium/Source/Core/defineProperties")
  .default;
var knockout = require("terriajs-cesium/Source/ThirdParty/knockout").default;
var ImageryLayerCatalogItem = require("./ImageryLayerCatalogItem");
var inherit = require("../Core/inherit");
var proxyCatalogItemUrl = require("./proxyCatalogItemUrl");
var WebMercatorTilingScheme = require("terriajs-cesium/Source/Core/WebMercatorTilingScheme")
  .default;

/**
 * A {@link ImageryLayerCatalogItem} representing a layer from the Open Street Map server.
 *
 * @alias OpenStreetMapCatalogItem
 * @constructor
 * @extends ImageryLayerCatalogItem
 *
 * @param {Terria} terria The Terria instance.
 */
var OpenStreetMapCatalogItem = function(terria) {

"use strict";

/*global require*/
var URI = require("urijs");

var clone = require("terriajs-cesium/Source/Core/clone").default;
var defined = require("terriajs-cesium/Source/Core/defined").default;
var defineProperties = require("terriajs-cesium/Source/Core/defineProperties")
  .default;
var freezeObject = require("terriajs-cesium/Source/Core/freezeObject").default;
var knockout = require("terriajs-cesium/Source/ThirdParty/knockout").default;
var loadJson = require("../Core/loadJson");
var when = require("terriajs-cesium/Source/ThirdParty/when").default;

var TerriaError = require("../Core/TerriaError");
var CatalogGroup = require("./CatalogGroup");
var inherit = require("../Core/inherit");
var proxyCatalogItemUrl = require("./proxyCatalogItemUrl");
var replaceUnderscores = require("../Core/replaceUnderscores");
var ArcGisMapServerCatalogItem = require("./ArcGisMapServerCatalogItem");

/**
 * A {@link CatalogGroup} representing a collection of layers from an ArcGIS Map Service.
 * Eg. http://www.ga.gov.au/gis/rest/services/earth_observation/Landcover_WM/MapServer
 *
 * @alias ArcGisMapServerCatalogGroup
 * @constructor

"use strict";

/*global require*/
var defined = require("terriajs-cesium/Source/Core/defined").default;
var defaultValue = require("terriajs-cesium/Source/Core/defaultValue").default;
var defineProperties = require("terriajs-cesium/Source/Core/defineProperties")
  .default;
var DeveloperError = require("terriajs-cesium/Source/Core/DeveloperError")
  .default;
var knockout = require("terriajs-cesium/Source/ThirdParty/knockout").default;
var CsvCatalogItem = require("./CsvCatalogItem");
var CatalogGroup = require("./CatalogGroup");
var USER_ADDED_CATEGORY_NAME = require("../Core/addedByUser")
  .USER_ADDED_CATEGORY_NAME;
var CHART_DATA_CATEGORY_NAME = require("../Core/addedForCharts")
  .CHART_DATA_CATEGORY_NAME;
var when = require("terriajs-cesium/Source/ThirdParty/when").default;

/**
 * The view model for the data catalog.
 *
 * @param {Terria} terria The Terria instance.
 *
 * @alias Catalog
 * @constructor
 */

"use strict";

/*global require*/

var knockout = require("terriajs-cesium/Source/ThirdParty/knockout").default;
var defined = require("terriajs-cesium/Source/Core/defined").default;

/**
 * Manages a stack of all the time series layers currently being shown and makes sure the clock provided is always tracking
 * the highest one. When the top-most layer is disabled, the clock will track the next highest in the stack. Provides access
 * to the current top layer so that can be displayed to the user.
 *
 * @param clock The clock that should track the highest layer.
 * @constructor
 */
var TimeSeriesStack = function(clock) {
  this.clock = clock;

  this._layerStack = [];

  knockout.track(this, ["_layerStack"]);

"use strict";

/*global require*/
var arraysAreEqual = require("../Core/arraysAreEqual");
var defaultValue = require("terriajs-cesium/Source/Core/defaultValue").default;
var defined = require("terriajs-cesium/Source/Core/defined").default;
var defineProperties = require("terriajs-cesium/Source/Core/defineProperties")
  .default;
var DeveloperError = require("terriajs-cesium/Source/Core/DeveloperError")
  .default;
var knockout = require("terriajs-cesium/Source/ThirdParty/knockout").default;
var runLater = require("../Core/runLater");
var serializeToJson = require("../Core/serializeToJson");
var updateFromJson = require("../Core/updateFromJson");
var TerriaError = require("../Core/TerriaError");

/**
 * A parameter to a {@link CatalogFunction}.
 *
 * @alias FunctionParameter
 * @constructor
 * @abstract
 *
 * @param {Object} [options] Object with the following properties:
 * @param {Terria} options.terria The Terria instance.
 * @param {CatalogFunction} options.catalogFunction The function that this is a parameter to.
 * @param {String} options.id The unique ID of this parameter.

"use strict";

/*global require*/
var URI = require("urijs");

var clone = require("terriajs-cesium/Source/Core/clone").default;
var defaultValue = require("terriajs-cesium/Source/Core/defaultValue").default;
var defined = require("terriajs-cesium/Source/Core/defined").default;
var defineProperties = require("terriajs-cesium/Source/Core/defineProperties")
  .default;
var freezeObject = require("terriajs-cesium/Source/Core/freezeObject").default;
var GeographicTilingScheme = require("terriajs-cesium/Source/Core/GeographicTilingScheme")
  .default;
var GetFeatureInfoFormat = require("terriajs-cesium/Source/Scene/GetFeatureInfoFormat")
  .default;
var knockout = require("terriajs-cesium/Source/ThirdParty/knockout").default;
var loadXML = require("../Core/loadXML");
var Rectangle = require("terriajs-cesium/Source/Core/Rectangle").default;
var WebMapTileServiceImageryProvider = require("terriajs-cesium/Source/Scene/WebMapTileServiceImageryProvider")
  .default;
var WebMercatorTilingScheme = require("terriajs-cesium/Source/Core/WebMercatorTilingScheme")
  .default;
var when = require("terriajs-cesium/Source/ThirdParty/when").default;

var containsAny = require("../Core/containsAny");
var Metadata = require("./Metadata");
var MetadataItem = require("./MetadataItem");
var ImageryLayerCatalogItem = require("./ImageryLayerCatalogItem");
var inherit = require("../Core/inherit");
var overrideProperty = require("../Core/overrideProperty");
var proxyCatalogItemUrl = require("./proxyCatalogItemUrl");
var xml2json = require("../ThirdParty/xml2json");

"use strict";

/*global require*/
var toGeoJSON = require("@mapbox/togeojson");

var defined = require("terriajs-cesium/Source/Core/defined").default;
var defineProperties = require("terriajs-cesium/Source/Core/defineProperties")
  .default;
var knockout = require("terriajs-cesium/Source/ThirdParty/knockout").default;
var when = require("terriajs-cesium/Source/ThirdParty/when").default;

var Metadata = require("./Metadata");
var TerriaError = require("../Core/TerriaError");
var CatalogItem = require("./CatalogItem");
var inherit = require("../Core/inherit");
var proxyCatalogItemUrl = require("./proxyCatalogItemUrl");

var GeoJsonCatalogItem = require("./GeoJsonCatalogItem");
var readText = require("../Core/readText");
var loadText = require("../Core/loadText");

/**
 * A {@link CatalogItem} representing GPX data.
 *
 * @alias GpxCatalogItem

"use strict";

/*global require*/
var URI = require("urijs");
var combine = require("terriajs-cesium/Source/Core/combine").default;

var clone = require("terriajs-cesium/Source/Core/clone").default;
var defined = require("terriajs-cesium/Source/Core/defined").default;
var defineProperties = require("terriajs-cesium/Source/Core/defineProperties")
  .default;
var freezeObject = require("terriajs-cesium/Source/Core/freezeObject").default;
var knockout = require("terriajs-cesium/Source/ThirdParty/knockout").default;
var loadJson = require("../Core/loadJson");
var loadXML = require("../Core/loadXML");

var GeoJsonCatalogItem = require("./GeoJsonCatalogItem");
var CatalogItem = require("./CatalogItem");
var inherit = require("../Core/inherit");
var gmlToGeoJson = require("../Map/gmlToGeoJson");
var overrideProperty = require("../Core/overrideProperty");
var proxyCatalogItemUrl = require("./proxyCatalogItemUrl");

/**
 * A {@link CatalogItem} representing a layer from a Web Feature Service (WFS) server.
 *
 * @alias WebFeatureServiceCatalogItem
 * @constructor
 * @extends CatalogItem

"use strict";

/*global require*/

var MetadataItem = require("./MetadataItem");
var knockout = require("terriajs-cesium/Source/ThirdParty/knockout").default;

/**
 * Represents the metadata associated with a data source.
 *
 * @alias Metadata
 * @constructor
 */
var Metadata = function() {
  /**
   * Gets or sets the metadata group for the data source itself.
   * @type {MetadataItem}
   */
  this.dataSourceMetadata = new MetadataItem();

  /**
   * Gets or sets the metadata group for the service