Auto merge of #5858 - pgonda:tabindex-focus-flag, r=jdm

Added support for the tabindex field, also added its correct defaults (-2 TODOs for things not supported in Servo yet).  Also added tabindex logic into Element::is_focusable_area.

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1 files changed, 8 insertions, 3 deletions

diff --git a/components/script/dom/element.rs b/components/script/dom/element.rs
index a666a28e627..b586172816d 100644
--- a/components/script/dom/element.rs
+++ b/components/script/dom/element.rs
@@ -54,7 +54,7 @@ use dom::htmltablecellelement::{HTMLTableCellElement, HTMLTableCellElementHelper
 use dom::htmltablerowelement::{HTMLTableRowElement, HTMLTableRowElementHelpers};
 use dom::htmltablesectionelement::{HTMLTableSectionElement, HTMLTableSectionElementHelpers};
 use dom::htmltextareaelement::{HTMLTextAreaElement, RawLayoutHTMLTextAreaElementHelpers};
-use dom::node::{CLICK_IN_PROGRESS, LayoutNodeHelpers, Node, NodeHelpers, NodeTypeId};
+use dom::node::{CLICK_IN_PROGRESS, LayoutNodeHelpers, Node, NodeHelpers, NodeTypeId, SEQUENTIALLY_FOCUSABLE};
 use dom::node::{document_from_node, NodeDamage};
 use dom::node::{window_from_node};
 use dom::nodelist::NodeList;
@@ -757,9 +757,11 @@ impl<'a> FocusElementHelpers for JSRef<'a, Element> {
             return false;
         }
         // TODO: Check whether the element is being rendered (i.e. not hidden).
-        // TODO: Check the tabindex focus flag.
-        // https://html.spec.whatwg.org/multipage/#specially-focusable
         let node: JSRef<Node> = NodeCast::from_ref(self);
+        if node.get_flag(SEQUENTIALLY_FOCUSABLE) {
+            return true;
+        }
+        // https://html.spec.whatwg.org/multipage/#specially-focusable
         match node.type_id() {
             NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLAnchorElement)) |
             NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLInputElement)) |
@@ -979,6 +981,9 @@ impl<'a> AttributeHandlers for JSRef<'a, Element> {
 
             self.attrs.borrow_mut().remove(idx);
             attr.r().set_owner(None);
+            if attr.r().namespace() == &ns!("") {
+                vtable_for(&NodeCast::from_ref(self)).after_remove_attr(attr.r().name());
+            }
 
             let node: JSRef<Node> = NodeCast::from_ref(self);
             if node.is_in_doc() {