Bug 1673199: Add a test whether it can access a filed in MediaList with normal privilege after accessing with chrome privilege. r=emilio

Differential Revision: https://phabricator.services.mozilla.com/D95257
2020-10-30 09:37:19 +00:00 · 2020-10-30 09:37:19 +00:00 · c3aace4366
--- a/layout/style/test/mochitest.ini
+++ b/layout/style/test/mochitest.ini
@ -412,3 +412,4 @@ skip-if = xorigin # Crashes, Assertion failure: mInFlightProcessId == 0, at /bui
 [test_non_matching_sheet_media.html]
 [test_use_counters.html]
 skip-if = !nightly_build
+[test_medialist_privilege.html]
--- a/layout/style/test/test_medialist_privilege.html
+++ b/layout/style/test/test_medialist_privilege.html
@ -0,0 +1,25 @@
+<!doctype html>
+<title>Test whether it can access a filed in MediaList with normal privilege after accessing with chrome privilege.</title>
+<script src="/tests/SimpleTest/SimpleTest.js"></script>
+
+<style>
+@media screen and (max-width: 800px) {
+  body {
+    background-color: lime;
+  }
+}
+</style>
+<script>
+"use strict";
+
+const chromeDocument = SpecialPowers.wrap(document);
+assertMediaText(chromeDocument);
+assertMediaText(document);
+
+function assertMediaText(doc) {
+  const stylesheet = doc.styleSheets[0];
+  const rule = stylesheet.cssRules[0];
+  const media = rule.media;
+  is(rule.media.mediaText, "screen and (max-width: 800px)");
+}
+</script>