third_party/WebKit/LayoutTests/editing/selection/select-line.html

<p>This tests for a crash when performing selectLine: inside an empty editable div.  It cannot be run manually.</p>
<div id="div" contenteditable="true"></div>

<script>
if (window.testRunner)
    window.testRunner.dumpAsText();
    
var div = document.getElementById("div");
var sel = window.getSelection();

sel.collapse(div, 0);
if (window.testRunner)
    testRunner.execCommand("SelectLine");
</script>