From ffa9ee3f6157754f584257e773b5133641a10c09 Mon Sep 17 00:00:00 2001
From: Wei-Cheng Pan <wpan@mozilla.com>
Date: Wed, 6 Sep 2017 15:40:54 +0800
Subject: [PATCH] Add a function to find out if a node has any ancestor that is
 pending for restyling.

---
 ports/geckolib/glue.rs | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/ports/geckolib/glue.rs b/ports/geckolib/glue.rs
index 3241e32bee1..e13fe3b64d2 100644
--- a/ports/geckolib/glue.rs
+++ b/ports/geckolib/glue.rs
@@ -3783,3 +3783,17 @@ pub extern "C" fn Servo_ProcessInvalidations(set: RawServoStyleSetBorrowed,
         }
     }
 }
+
+#[no_mangle]
+pub extern "C" fn Servo_HasPendingRestyleAncestor(element: RawGeckoElementBorrowed) -> bool {
+    let mut element = Some(GeckoElement(element));
+    while let Some(e) = element {
+        if let Some(data) = e.borrow_data() {
+            if data.restyle.hint.has_non_animation_invalidations() {
+                return true;
+            }
+        }
+        element = e.traversal_parent();
+    }
+    false
+}