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chromium/third_party/blink/web_tests/paint/invalidation/overflow/overflow-hidden-to-visible.html 

<!DOCTYPE html>
Tests paint invalidation of overflowing contents when the container's overflow changes from hidden to visible.
Passes if there is no red.
<div id="indicator" style="position: absolute; z-index: -1; width: 200px; height: 400px; background-color: red"></div>
<div id="container" style="width: 200px; height: 200px; overflow: hidden">
  <div style="width: 0; height: 0">
    <div id="green" style="width: 200px; height: 400px; background-color: green"></div>
  </div>
</div>
<script src="../../../resources/run-after-layout-and-paint.js"></script>
<script>
runAfterLayoutAndPaint(function() {
   container.style.overflow = 'visible';
}, true);
</script>