Only handle most recent resize event in script thread (#33297)

This avoids having to do unnecessary layout work and
prevents resize events from accumulating, which looks
weird.

Signed-off-by: Simon Wülker <simon.wuelker@arcor.de>

components/script/script_thread.rs

@@ -1688,7 +1688,7 @@ impl ScriptThread {
             // TODO(#31665): Implement the "run the scroll steps" from
             // https://drafts.csswg.org/cssom-view/#document-run-the-scroll-steps.
 
-            for (size, size_type) in document.window().steal_resize_events().into_iter() {
+            if let Some((size, size_type)) = document.window().take_unhandled_resize_event() {
                 // Resize steps.
                 self.run_the_resize_steps(pipeline_id, size, size_type);