Expose navigator.appCodeName and navigator.product in Worker

Tests: web-platform-tests/wpt#3881

Follow up to #216.

source

@@ -90986,11 +90986,11 @@ scheduleWork(); // queues a task to do lots of work</pre>
 
   <pre class="idl">[NoInterfaceObject, Exposed=(Window,Worker)]
 interface <dfn>NavigatorID</dfn> {
-  [Exposed=Window] readonly attribute DOMString <span data-x="dom-navigator-appCodeName">appCodeName</span>; // constant "Mozilla"
+  readonly attribute DOMString <span data-x="dom-navigator-appCodeName">appCodeName</span>; // constant "Mozilla"
   readonly attribute DOMString <span data-x="dom-navigator-appName">appName</span>; // constant "Netscape"
   readonly attribute DOMString <span data-x="dom-navigator-appVersion">appVersion</span>;
   readonly attribute DOMString <span data-x="dom-navigator-platform">platform</span>;
-  [Exposed=Window] readonly attribute DOMString <span data-x="dom-navigator-product">product</span>; // constant "Gecko"
+  readonly attribute DOMString <span data-x="dom-navigator-product">product</span>; // constant "Gecko"
   [Exposed=Window] readonly attribute DOMString <span data-x="dom-navigator-productSub">productSub</span>;
   readonly attribute DOMString <span data-x="dom-navigator-userAgent">userAgent</span>;
   [Exposed=Window] readonly attribute DOMString <span data-x="dom-navigator-vendor">vendor</span>;