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chromium/third_party/blink/web_tests/compositing/overflow/rotate-clip.html 

<!DOCTYPE html>
<div style="margin: 100px; transform: rotate(45deg); overflow: hidden;
            width: 200px; height: 200px; border: 20px solid green">
  <div style="will-change: transform; width: 400px; height: 400px; background: blue"></div>
</div>
<script>
if (window.testRunner)
  testRunner.setCustomTextOutput(internals.layerTreeAsText(document));
</script>