1 files changed, 60 insertions, 0 deletions
diff --git a/layout/base/tests/test_bug990340.html b/layout/base/tests/test_bug990340.html
new file mode 100644
index 000000000..8d9984fbe
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+++ b/layout/base/tests/test_bug990340.html
@@ -0,0 +1,60 @@
+<!DOCTYPE HTML>
+<html>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=990340
+-->
+<head>
+  <meta charset="utf-8">
+  <title>Test for Bug 990340</title>
+  <script type="application/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
+  <script type="application/javascript">
+
+  /** Test for Bug 990340 **/
+
+  function testbug990340() {
+    ok(document.querySelector('#bug990340 span').clientHeight < 100,
+       "'height' is in transition")
+    SimpleTest.finish();
+  }
+
+  SimpleTest.waitForExplicitFinish();
+  </script>
+</head>
+<body>
+<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=990340">Mozilla Bug 990340</a>
+<p id="display"></p>
+<div id="content" style="display: none">
+
+</div>
+<pre id="test">
+<style type="text/css">
+
+#bug990340::before {
+    content: ":before";
+}
+
+#bug990340 span {
+    display: inline-block;
+    border:1px solid blue;
+    height: 20px;
+    transition: height 30s;
+}
+
+#bug990340.s span {
+    height: 100px;
+}
+</style>
+<div id="bug990340" style="overflow:scroll">
+    <span>Transition height</span>
+</div>
+</pre>
+
+<script>
+document.body.offsetHeight;
+document.querySelector('#bug990340').className='s';
+testbug990340()
+</script>
+
+</body>
+</html>