From 5ddf455235be2a31d10ef388572a35d2433361ae Mon Sep 17 00:00:00 2001
From: Boris Zbarsky <bzbarsky@mit.edu>
Date: Mon, 15 May 2017 15:55:05 -0400
Subject: [PATCH] Fix style sharing cache lookups to compare ids of the two
 elements.

Otherwise we can have a situation like this:

  <style>
    .notmatching > #foo {}
  </style>
  <span id="foo"></span>
  <span></span>

and the style sharing cache lookup for the second <span> would try to revalidate
against the cached value for the first <span>, but end up failing asserts about
the two elements matching lists of revalidation selectors that have the same
length.
---
 components/style/matching.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/components/style/matching.rs b/components/style/matching.rs
index 530b3c1f591..4e336c25002 100644
--- a/components/style/matching.rs
+++ b/components/style/matching.rs
@@ -176,7 +176,7 @@ fn element_matches_candidate<E: TElement>(element: &E,
         miss!(State)
     }
 
-    if element.get_id().is_some() {
+    if element.get_id() != candidate_element.get_id() {
         miss!(IdAttr)
     }