LayoutTests/webanimations/offset-shorthand-animation-yields-compositing.html

<pre id="results"></pre>
<div id="target" style="width: 100px; height: 100px; background-color: black;"></div>
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testRunner.dumpAsText();

document.getElementById("target").animate({
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    document.getElementById("results").innerText = internals.layerTreeAsText(document);
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