Auto merge of #9763 - Tangresh:i9725, r=nox

Implement value for DOMTokenList

Fixes #9725

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components/script/dom/domtokenlist.rs

@@ -129,6 +129,16 @@ impl DOMTokenListMethods for DOMTokenList {
         }
     }
 
+    // https://dom.spec.whatwg.org/#dom-domtokenlist-value
+    fn Value(&self) -> DOMString {
+        self.element.get_string_attribute(&self.local_name)
+    }
+
+    // https://dom.spec.whatwg.org/#dom-domtokenlist-value
+    fn SetValue(&self, value: DOMString) {
+        self.element.set_tokenlist_attribute(&self.local_name, value);
+    }
+
     // https://dom.spec.whatwg.org/#concept-dtl-serialize
     fn Stringifier(&self) -> DOMString {
         self.element.get_string_attribute(&self.local_name)

components/script/dom/webidls/DOMTokenList.webidl

@@ -19,5 +19,8 @@ interface DOMTokenList {
   [Throws]
   boolean toggle(DOMString token, optional boolean force);
 
+  [Pure]
+           attribute DOMString value;
+
   stringifier;
 };

components/script/dom/webidls/Element.webidl

@@ -28,7 +28,7 @@ interface Element : Node {
            attribute DOMString id;
   [Pure]
            attribute DOMString className;
-  [SameObject]
+  [SameObject, PutForwards=value]
   readonly attribute DOMTokenList classList;
 
   [SameObject]