style: Remove NODE_IS_ANONYMOUS_ROOT.

We no longer have multiple kinds of anonymous subtrees, so we can get back one
node bit.

Differential Revision: https://phabricator.services.mozilla.com/D53344

components/style/gecko/wrapper.rs

@@ -761,25 +761,13 @@ impl<'le> GeckoElement<'le> {
         data.damage |= damage;
     }
 
-    /// This logic is duplicated in Gecko's nsIContent::IsRootOfAnonymousSubtree.
-    #[inline]
-    fn is_root_of_anonymous_subtree(&self) -> bool {
-        use crate::gecko_bindings::structs::NODE_IS_ANONYMOUS_ROOT;
-        self.flags() & (NODE_IS_ANONYMOUS_ROOT as u32) != 0
-    }
-
     /// This logic is duplicated in Gecko's nsIContent::IsRootOfNativeAnonymousSubtree.
     #[inline]
     fn is_root_of_native_anonymous_subtree(&self) -> bool {
         use crate::gecko_bindings::structs::NODE_IS_NATIVE_ANONYMOUS_ROOT;
         return self.flags() & (NODE_IS_NATIVE_ANONYMOUS_ROOT as u32) != 0;
     }
 
-    #[inline]
-    fn is_in_anonymous_subtree(&self) -> bool {
-        unsafe { bindings::Gecko_IsInAnonymousSubtree(self.0) }
-    }
-
     /// Returns true if this node is the shadow root of an use-element shadow tree.
     #[inline]
     fn is_root_of_use_element_shadow_tree(&self) -> bool {
@@ -1028,7 +1016,7 @@ impl<'le> TElement for GeckoElement<'le> {
         // StyleChildrenIterator::IsNeeded does, except that it might return
         // true if we used to (but no longer) have anonymous content from
         // ::before/::after, or nsIAnonymousContentCreators.
-        if self.is_in_anonymous_subtree() ||
+        if self.is_in_native_anonymous_subtree() ||
             self.is_html_slot_element() ||
             self.shadow_root().is_some() ||
             self.may_have_anonymous_children()
@@ -2243,7 +2231,7 @@ impl<'le> ::selectors::Element for GeckoElement<'le> {
 
     #[inline]
     fn ignores_nth_child_selectors(&self) -> bool {
-        self.is_root_of_anonymous_subtree()
+        self.is_root_of_native_anonymous_subtree()
     }
 }