From 36bac588630c6b49f20fea176a8e81c7bff7442b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Emilio=20Cobos=20=C3=81lvarez?= <emilio@crisal.io>
Date: Mon, 12 Jun 2017 04:51:00 +0200
Subject: [PATCH] style: Don't try to go down the tree if there aren't
 invalidations.

This can happen when adding an empty stylesheet, for example.

Bug: 1372068
MozReview-Commit-ID: Jtm4eJBWjEA
---
 components/style/invalidation/stylesheets.rs | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/components/style/invalidation/stylesheets.rs b/components/style/invalidation/stylesheets.rs
index 6d36d16a2cd..c1014d0383b 100644
--- a/components/style/invalidation/stylesheets.rs
+++ b/components/style/invalidation/stylesheets.rs
@@ -155,6 +155,11 @@ impl StylesheetInvalidationSet {
             return true;
         }
 
+        if self.invalid_scopes.is_empty() {
+            debug!("process_invalidations_in_subtree: empty invalidation set");
+            return false;
+        }
+
         for scope in &self.invalid_scopes {
             if scope.matches(element) {
                 debug!("process_invalidations_in_subtree: {:?} matched {:?}",