chromium/third_party/blink/web_tests/fast/events/hit-test-cache-scrollbar-no-crash.html

<!DOCTYPE html>
<meta name="viewport" content="width=device-width, initial-scale=1">
<script>
if (window.internals)
    internals.useMockOverlayScrollbars();
</script>
<style>
#parent {
  overflow: scroll;
  height: 400px;
}
#testarea {
  height: 6000px;
  background: red;
}
</style>
<div id="parent"><div id="testarea"/></div>
<br>
<script src="../../resources/js-test.js"></script>
<script>

description("Ensure hit test cache works in correct scenarios of overlay scrollbars.");

if (window.internals) {
    var parentDiv = document.getElementById("parent");
    var rect = parentDiv.getBoundingClientRect();

    // Only MacOSX > 10.6 has overlay scrollbars; so the result will be 1 on other platforms.
    var expectedCount = internals.setScrollbarVisibilityInScrollableArea(parentDiv, true) ? 0 : 1;
    internals.elementFromPoint(document, rect.left + rect.width - 2, rect.top + (rect.height/2), false, false);
    internals.setScrollbarVisibilityInScrollableArea(parentDiv, false);
    internals.elementFromPoint(document, rect.left + rect.width - 2, rect.top + (rect.height/2), false, false);
    shouldBe("internals.hitTestCacheHits(document)", "expectedCount");
}
</script>