Auto merge of #10762 - canaltinova:has_attributes, r=nox

Implement Element::hasAttributes

Fixes #10748 .
Implement Element::hasAttributes. I'm not sure if tests are enough. I'm open to suggestion :)

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components/script/dom/element.rs

@@ -1335,6 +1335,11 @@ impl ElementMethods for Element {
         self.attr_list.or_init(|| NamedNodeMap::new(&window_from_node(self), self))
     }
 
+    // https://dom.spec.whatwg.org/#dom-element-hasattributes
+    fn HasAttributes(&self) -> bool {
+        !self.attrs.borrow().is_empty()
+    }
+
     // https://dom.spec.whatwg.org/#dom-element-getattributenames
     fn GetAttributeNames(&self) -> Vec<DOMString> {
         self.attrs.borrow().iter().map(|attr| attr.Name()).collect()

components/script/dom/webidls/Element.webidl

@@ -35,6 +35,8 @@ interface Element : Node {
   [Pure]
   sequence<DOMString> getAttributeNames();
   [Pure]
+  boolean hasAttributes();
+  [Pure]
   DOMString? getAttribute(DOMString name);
   [Pure]
   DOMString? getAttributeNS(DOMString? namespace, DOMString localName);