chromium/third_party/blink/web_tests/fast/layers/assert-RenderLayer-update-positions.html

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                        <h3>Test for bug 66901. The test passes if it does not <span>ASSERT.</span></h3>
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                <script>
                    if (window.testRunner) {
                        testRunner.dumpAsText();
                        testRunner.waitUntilDone();
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                    function assert() {
                        var dimensionsContainer = document.getElementById("assertTrigger");
                        dimensionsContainer.setAttribute("class", "");
                        if (window.testRunner)
                            testRunner.notifyDone();
                    }

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                    window.setTimeout(assert, 0);
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