LayoutTests/editing/pasteboard/merge-start-blockquote.html

<script>
if (window.testRunner)
     testRunner.dumpEditingCallbacks();
</script>
<style>
blockquote {
    border: 1px solid blue;
}
</style>

<p>This test makes sure that content inside a Mail blockquote in an incoming fragment isn't pulled out of the blockquote during paste.</p>
<p><b>You should see 'bar' inside a blockquote (it will have a blue border around it if it is).</b></p>

<div id="test" contenteditable="true"></div>

<script>
var s = window.getSelection();
var e = document.getElementById("test");

s.setPosition(e, 0);

document.execCommand("InsertHTML", false , "<blockquote type='cite'>bar</blockquote>");
</script>