Typecheck some of ui/webui/resources/js/ with Closure compiler.

ui/webui/resources/js/cr.js

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+<include src="assert.js">
+
 /**
  * The global object.
  * @type {!Object}
  * @const
  */
 var global = this;
 
 /** Platform, package, object property, and Event support. **/
-this.cr = (function() {
+var cr = (function() {
   'use strict';
 
   /**
    * Builds an object structure for the provided namespace path,
    * ensuring that names that already exist are not overwritten. For
    * example:
    * "a.b.c" -> a = {};a.b={};a.b.c={};
    * @param {string} name Name of the object that this file defines.
    * @param {*=} opt_object The object to expose at the end of the path.
    * @param {Object=} opt_objectToExportTo The object to add the path to;
@@ skipping 37 matching lines @@
    * attribute name.
    * @param {string} jsName The javascript camelCase property name.
    * @return {string} The equivalent hyphenated-lower-case attribute name.
    */
   function getAttributeName(jsName) {
     return jsName.replace(/([A-Z])/g, '-$1').toLowerCase();
   }
 
   /**
    * The kind of property to define in {@code defineProperty}.
-   * @enum {number}
+   * @enum {string}
    * @const
    */
   var PropertyKind = {
     /**
      * Plain old JS property where the backing data is stored as a "private"
      * field on the object.
      */
     JS: 'js',
 
     /**
      * The property backing data is stored as an attribute on an element.
      */
     ATTR: 'attr',
 
     /**
      * The property backing data is stored as an attribute on an element. If the
      * element has the attribute then the value is true.
      */
     BOOL_ATTR: 'boolAttr'
   };
 
   /**
    * Helper function for defineProperty that returns the getter to use for the
    * property.
    * @param {string} name The name of the property.
-   * @param {cr.PropertyKind} kind The kind of the property.
+   * @param {PropertyKind} kind The kind of the property.
    * @return {function():*} The getter for the property.
    */
   function getGetter(name, kind) {
     switch (kind) {
       case PropertyKind.JS:
         var privateName = name + '_';
         return function() {
           return this[privateName];
         };
       case PropertyKind.ATTR:
         var attributeName = getAttributeName(name);
         return function() {
           return this.getAttribute(attributeName);
         };
       case PropertyKind.BOOL_ATTR:
         var attributeName = getAttributeName(name);
         return function() {
           return this.hasAttribute(attributeName);
         };
     }
+
+    assertNotReached();
+    return function() {};
   }
 
   /**
    * Helper function for defineProperty that returns the setter of the right
    * kind.
    * @param {string} name The name of the property we are defining the setter
    *     for.
-   * @param {cr.PropertyKind} kind The kind of property we are getting the
+   * @param {PropertyKind} kind The kind of property we are getting the
    *     setter for.
-   * @param {function(*):void} opt_setHook A function to run after the property
+   * @param {function():void=} opt_setHook A function to run after the property
    *     is set, but before the propertyChange event is fired.
    * @return {function(*):void} The function to use as a setter.
    */
   function getSetter(name, kind, opt_setHook) {
     switch (kind) {
       case PropertyKind.JS:
         var privateName = name + '_';
         return function(value) {
           var oldValue = this[name];
           if (value !== oldValue) {
@@ skipping 27 matching lines @@
             if (value)
               this.setAttribute(attributeName, name);
             else
               this.removeAttribute(attributeName);
             if (opt_setHook)
               opt_setHook.call(this, value, oldValue);
             dispatchPropertyChange(this, name, value, oldValue);
           }
         };
     }
+
+    assertNotReached();
+    return function() {};
   }
 
   /**
    * Defines a property on an object. When the setter changes the value a
    * property change event with the type {@code name + 'Change'} is fired.
    * @param {!Object} obj The object to define the property for.
    * @param {string} name The name of the property.
-   * @param {cr.PropertyKind=} opt_kind What kind of underlying storage to use.
-   * @param {function(*):void} opt_setHook A function to run after the
+   * @param {PropertyKind=} opt_kind What kind of underlying storage to use.
+   * @param {function(*):void=} opt_setHook A function to run after the
    *     property is set, but before the propertyChange event is fired.
    */
   function defineProperty(obj, name, opt_kind, opt_setHook) {
     if (typeof obj == 'function')
       obj = obj.prototype;
 
-    var kind = opt_kind || PropertyKind.JS;
+    var kind = /** @type {PropertyKind} */ (opt_kind || PropertyKind.JS);
 
     if (!obj.__lookupGetter__(name))
       obj.__defineGetter__(name, getGetter(name, kind));
 
     if (!obj.__lookupSetter__(name))
       obj.__defineSetter__(name, getSetter(name, kind, opt_setHook));
   }
 
   /**
    * Counter for use with createUid
@@ skipping 144 matching lines @@
     PropertyKind: PropertyKind
   };
 })();
 
 
 /**
  * TODO(kgr): Move this to another file which is to be loaded last.
  * This will be done as part of future work to make this code pre-compilable.
  */
 cr.initialize();