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chromium/third_party/blink/web_tests/paint/invalidation/button-spurious-layout-hint.html 

<head>
    <script src="resources/text-based-repaint.js" type="text/javascript"></script>
    <script>
        function repaintTest()
        {
            document.getElementById("target").style.backgroundColor = "lightpink";
        }
    </script>
</head>
<body onload="runRepaintAndPixelTest()">
    <button id="target" style="height: 100px; width: 100px; background-color: lightblue; border: none;">&nbsp;</button>
</body>