Auto merge of #13172 - bholley:display_enum, r=emilio

stylo: avoid traversing non element/text nodes in style and layout

r? @emilio

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1 files changed, 6 insertions, 9 deletions

diff --git a/components/script_layout_interface/wrapper_traits.rs b/components/script_layout_interface/wrapper_traits.rs
index 20ddca94cf4..dcb1f68cfb4 100644
--- a/components/script_layout_interface/wrapper_traits.rs
+++ b/components/script_layout_interface/wrapper_traits.rs
@@ -15,7 +15,7 @@ use std::sync::Arc;
 use string_cache::{Atom, Namespace};
 use style::computed_values::display;
 use style::context::SharedStyleContext;
-use style::dom::{PresentationalHintsSynthetizer, TNode};
+use style::dom::{LayoutIterator, NodeInfo, PresentationalHintsSynthetizer, TNode};
 use style::dom::OpaqueNode;
 use style::properties::ServoComputedValues;
 use style::refcell::{Ref, RefCell};
@@ -81,10 +81,10 @@ pub trait LayoutNode: TNode {
     fn init_style_and_layout_data(&self, data: OpaqueStyleAndLayoutData);
     fn get_style_and_layout_data(&self) -> Option<OpaqueStyleAndLayoutData>;
 
-    fn rev_children(self) -> ReverseChildrenIterator<Self> {
-        ReverseChildrenIterator {
+    fn rev_children(self) -> LayoutIterator<ReverseChildrenIterator<Self>> {
+        LayoutIterator(ReverseChildrenIterator {
             current: self.last_child(),
-        }
+        })
     }
 
     fn traverse_preorder(self) -> TreeIterator<Self> {
@@ -137,7 +137,7 @@ impl<ConcreteNode> Iterator for TreeIterator<ConcreteNode>
 
 /// A thread-safe version of `LayoutNode`, used during flow construction. This type of layout
 /// node does not allow any parents or siblings of nodes to be accessed, to avoid races.
-pub trait ThreadSafeLayoutNode: Clone + Copy + Sized + PartialEq {
+pub trait ThreadSafeLayoutNode: Clone + Copy + NodeInfo + PartialEq + Sized {
     type ConcreteThreadSafeLayoutElement:
         ThreadSafeLayoutElement<ConcreteThreadSafeLayoutNode = Self>
         + ::selectors::Element<Impl=ServoSelectorImpl>;
@@ -169,10 +169,7 @@ pub trait ThreadSafeLayoutNode: Clone + Copy + Sized + PartialEq {
     fn debug_id(self) -> usize;
 
     /// Returns an iterator over this node's children.
-    fn children(&self) -> Self::ChildrenIterator;
-
-    #[inline]
-    fn is_element(&self) -> bool { if let Some(LayoutNodeType::Element(_)) = self.type_id() { true } else { false } }
+    fn children(&self) -> LayoutIterator<Self::ChildrenIterator>;
 
     /// If this is an element, accesses the element data. Fails if this is not an element node.
     #[inline]