Implement Element#closest

fixes #4603

- Add definition to the Element.webidl and implementation to element.rs.
- Create inclusive_ancestors helper in NodeHelpers
- Update test expectations

1 files changed, 7 insertions, 0 deletions

diff --git a/components/script/dom/node.rs b/components/script/dom/node.rs
index bc44aeda8ba..fb336efd85b 100644
--- a/components/script/dom/node.rs
+++ b/components/script/dom/node.rs
@@ -397,6 +397,7 @@ impl<'a> Iterator<JSRef<'a, Node>> for QuerySelectorIterator<'a> {
 
 pub trait NodeHelpers<'a> {
     fn ancestors(self) -> AncestorIterator<'a>;
+    fn inclusive_ancestors(self) -> AncestorIterator<'a>;
     fn children(self) -> NodeChildrenIterator<'a>;
     fn rev_children(self) -> ReverseChildrenIterator;
     fn child_elements(self) -> ChildElementIterator<'a>;
@@ -798,6 +799,12 @@ impl<'a> NodeHelpers<'a> for JSRef<'a, Node> {
         }
     }
 
+    fn inclusive_ancestors(self) -> AncestorIterator<'a> {
+        AncestorIterator {
+            current: Some(self.clone())
+        }
+    }
+
     fn owner_doc(self) -> Temporary<Document> {
         self.owner_doc.get().unwrap()
     }