chromium/src/third_party/blink/web_tests/editing/selection/removeAllRanges.html

<p>This tests Selection::removeAllRanges().</p>
<div id="div">This should not be selected.</div>

<script>
if (window.testRunner) {
    testRunner.dumpEditingCallbacks();
    testRunner.dumpAsText();
}
var sel = window.getSelection();
var div = document.getElementById("div");
div.focus();
document.execCommand("SelectAll");
sel.removeAllRanges();
</script>