Auto merge of #13145 - ashrko619:nav-cookie-enabled, r=nox

Implemented Navigator.cookieEnabled

<!-- Please describe your changes on the following line: -->

---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: -->
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #13124 (github issue number if applicable).

<!-- Either: -->
- [x] There are tests for these changes.

<!-- Pull requests that do not address these steps are welcome, but they will require additional verification as part of the review process. -->

<!-- Reviewable:start -->
---
This change is [<img src="https://reviewable.io/review_button.svg" height="34" align="absmiddle" alt="Reviewable"/>](https://reviewable.io/reviews/servo/servo/13145)
<!-- Reviewable:end -->

components/script/dom/navigator.rs

@@ -107,4 +107,10 @@ impl NavigatorMethods for Navigator {
     fn ServiceWorker(&self) -> Root<ServiceWorkerContainer> {
         self.serviceWorker.or_init(|| ServiceWorkerContainer::new(self.global().r()))
     }
+
+    // https://html.spec.whatwg.org/multipage/#dom-navigator-cookieenabled
+    fn CookieEnabled(&self) -> bool {
+        true
+    }
+
 }

components/script/dom/webidls/Navigator.webidl

@@ -14,6 +14,7 @@ Navigator implements NavigatorLanguage;
 //Navigator implements NavigatorContentUtils;
 //Navigator implements NavigatorStorageUtils;
 Navigator implements NavigatorPlugins;
+Navigator implements NavigatorCookies;
 
 // https://html.spec.whatwg.org/multipage/#navigatorid
 [NoInterfaceObject, Exposed=(Window,Worker)]
@@ -52,3 +53,9 @@ interface NavigatorPlugins {
   [SameObject] readonly attribute MimeTypeArray mimeTypes;
   boolean javaEnabled();
 };
+
+// https://html.spec.whatwg.org/multipage/#navigatorcookies
+[NoInterfaceObject, Exposed=(Window,Worker)]
+interface NavigatorCookies {
+  readonly attribute boolean cookieEnabled;
+};