Auto merge of #12862 - servo:layout-new, r=emilio

added dom obj counting to decide sequential/parallel layout (#10110)

This is a rebased version of #11713

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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #10110 (github issue number if applicable).
- [X] There are no tests for these changes because it's an optimization with no visible behavioral changes

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1 files changed, 4 insertions, 1 deletions

diff --git a/components/script/dom/htmlheadelement.rs b/components/script/dom/htmlheadelement.rs
index 419644c5bb3..fc6e888d015 100644
--- a/components/script/dom/htmlheadelement.rs
+++ b/components/script/dom/htmlheadelement.rs
@@ -71,7 +71,10 @@ impl VirtualMethods for HTMLHeadElement {
     fn super_type(&self) -> Option<&VirtualMethods> {
         Some(self.upcast::<HTMLElement>() as &VirtualMethods)
     }
-    fn bind_to_tree(&self, _tree_in_doc: bool) {
+    fn bind_to_tree(&self, tree_in_doc: bool) {
+        if let Some(ref s) = self.super_type() {
+            s.bind_to_tree(tree_in_doc);
+        }
         load_script(self);
     }
 }