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chromium
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chromium/third_party/blink/web_tests/fast/css/outline-negative.html 

<html>
    <script>
        if (window.testRunner)
            testRunner.dumpAsText();
    </script>
    <body>
        <a style="outline: solid; outline-offset: -70px;">PASS</a>
    </body>
</html>