Auto merge of #12563 - emilio:stylo, r=bholley,jdm,pcwalton

stylo: Improve restyling performance

This commit adds hooks to the Servo style traversal to avoid traversing all the
DOM for every restyle. Additionally it changes the behavior of the dirty flag to
be propagated top down, to prevent extra overhead when an element is dirtied.

This commit doesn't aim to change the behavior on Servo just yet, since Servo does extra job when dirtying the node related with DOM revision counters that might be necessary.

CC @asajeffrey for the DOM revision counters stuff. When a node is dirty, do all its descendants really need to increment the revision counter, or is this an unintended effect? My intuition is that this is hurting performance quite a lot for servo.

r? @bholley

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1 files changed, 0 insertions, 2 deletions

diff --git a/components/script/script_thread.rs b/components/script/script_thread.rs
index d5d23578c7a..e3d2766c84c 100644
--- a/components/script/script_thread.rs
+++ b/components/script/script_thread.rs
@@ -1198,8 +1198,6 @@ impl ScriptThread {
         // https://html.spec.whatwg.org/multipage/#the-end step 7
         let handler = box DocumentProgressHandler::new(Trusted::new(doc));
         self.dom_manipulation_task_source.queue(handler, GlobalRef::Window(doc.window())).unwrap();
-
-        self.constellation_chan.send(ConstellationMsg::LoadComplete(pipeline)).unwrap();
     }
 
     fn collect_reports(&self, reports_chan: ReportsChan) {